Topic: [ANN][GRS] Groestlcoin | 1st to activate Segwit | Building Lightning Network - page 9. (Read 558266 times)

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If you are an ordinary user of Groestlcoin and simply want the convenience of a web wallet with the security of a real application and support for multi-signature, then Elecrum-GRS is the right choice for you.

Changelog Electrum-GRS 4.0.7
• PSBT: restore compatibility with Groestlcoin Core following CVE-2020-14199: we now allow a PSBT input to have both UTXO and WITNESS_UTXO. (PSBTs created since 4.0.2 already contained UTXO for segwit inputs).
• New feature: "Automated BIP39 recovery". When restoring from a BIP39 seed, add option to scan many known derivation paths for history, and show them to user to choose from.
• New feature: "Cancel tx". The Qt/kivy GUI allows cancelling an unconfirmed RBF tx by double-spending its inputs to self.
• Lightning:
   - bugfix: during LN channel opening, if the client crashed at the wrong moment, the channel might not get fully persisted to disk, and would need manual console-tinkering to recover.
   - Lightning is enabled by default. Electrum-GRS will not connect to the Lightning Network until the user opens a channel.
   - smarter node recommendation (to open channels with).
• Fix 'Max' button in kivy.
• Various fixes for Kivy/Android install wizard.
• Kivy: fix open channel with 'max' amount.
• Dependencies (as part of adapting to new dnspython):
   - pyaes is no longer needed.
   - python-ecdsa is no longer needed at all.
   - cryptography is now required (min 2.6), the user can no longer choose between cryptography and pycryptodomex.

Features
• Encrypted wallet - the file that contains your groestlcoins is protected with a password. You are protected from thieves.
• Deterministic key generation - If you lose your wallet, you can recover it from its seed. You are protected from your own mistakes.
• Instant on - the client does not download the blockchain, it requests that information from a server. No delays, always up-to-date.
• Freedom and Privacy - The server does not store user accounts. You are not tied to a particular server, and the server does not need to know you.
• No scripts - Electrum-GRS does not download any script. A compromised server cannot send you arbitrary code and steal your groestlcoins.
• No single point of failure - The server code is open source, anyone can run a server.
• Transactions are signed locally - Your private keys are not shared with the server. You do not have to trust the server with your money.
• Firewall friendly - The client does not need to open a port, it simply polls the server for updates.
• Free software - Gnu GPL v3. Anyone can audit the code.
• Written in Python - The code is short, and easy to review.
• User Friendly - Support for Groestlcoin URIs, signed URIs and Groestlcoin aliases
• No Lock-In - You can export your private keys and use them in other groestlcoin clients.
• No Downtimes - Electrum-GRS servers are decentralized and redundant. Your wallet is never down.
• Proof Checking - Electrum-GRS Wallet verifies all the transactions in your history using SPV.
• Cold Storage - Keep your private keys offline, and go online with a watching-only wallet. Sign transactions from a computer that is always offline. Broadcast them from a machine that does not have your keys.
• Multisign - Split the permission to spend your coins between several wallets using parallel BIP32 derivations and P2SH addresses ("2 of 2", "2 of 3"). Compact serialization format for unsigned or partially signed transactions, that includes the BIP32 master public key and derivation needed to sign inputs. Serialized transactions can be sent to cosigners or to cold storage using QR codes

This application is licensed under the GPL version 3. There is no warranty and no party shall be made liable to you for damages. If you lose coins due to this app, no compensation will be given. Use this app solely at your own risk.

Important:
Store your secret phrase somewhere safe!
The multi-signature and non native segwit addresses starts with a "3" and not with a "F".

Electrum-GRS is available in the Google play store:
https://play.google.com/store/apps/details?id=org.groestlcoin.electrumgrs

Source code:
GitHub Source server: https://github.com/Groestlcoin/electrumx-grs
Github Source server installer: https://github.com/Groestlcoin/electrumx-grs-installer
Github Source client: https://github.com/Groestlcoin/electrum-grs

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If you are an ordinary user of Groestlcoin and simply want the convenience of a web wallet with the security of a real application and support for multi-signature, then Elecrum-GRS is the right choice for you.

Changelog Electrum-GRS 4.0.7
• PSBT: restore compatibility with Groestlcoin Core following CVE-2020-14199: we now allow a PSBT input to have both UTXO and WITNESS_UTXO. (PSBTs created since 4.0.2 already contained UTXO for segwit inputs).
• Hardware wallets: run all device communication on a dedicated thread.
• New feature: "Automated BIP39 recovery". When restoring from a BIP39 seed, add option to scan many known derivation paths for history, and show them to user to choose from.
• Show derivation path of keystores in Qt GUI Wallet>Information.
• Fix "signtransaction" RPC command.
• The tar.gz source dist now bundles make_libsecp256k1.sh, to help users getting libsecp256k1.
• New feature: "Cancel tx". The Qt/kivy GUI allows cancelling an unconfirmed RBF tx by double-spending its inputs to self.
• Windows binary:
   - fix some issues with QR scanning by building zbar ourselves.
   - when using setup exe, also install a debug binary.
• Fix .dmg binary hanging on recently released macOS 11 Big Sur.
• Lightning:
   - bugfix: during LN channel opening, if the client crashed at the wrong moment, the channel might not get fully persisted to disk, and would need manual console-tinkering to recover.
   - Lightning is enabled by default. Electrum-GRS will not connect to the Lightning Network until the user opens a channel.
   - smarter node recommendation (to open channels with).
• Fix 'Max' button issue for submarine swaps button.
• Fix 'Max' button in kivy.
• Various fixes for Kivy/Android install wizard.
• Kivy: fix open channel with 'max' amount.
• Dependencies (as part of adapting to new dnspython):
   - pyaes is no longer needed.
   - python-ecdsa is no longer needed at all.
   - cryptography is now required (min 2.6), the user can no longer choose between cryptography and pycryptodomex.

Features
• Encrypted wallet - the file that contains your groestlcoins is protected with a password. You are protected from thieves.
• Deterministic key generation - If you lose your wallet, you can recover it from its seed. You are protected from your own mistakes.
• Instant on - the client does not download the blockchain, it requests that information from a server. No delays, always up-to-date.
• Freedom and Privacy - The server does not store user accounts. You are not tied to a particular server, and the server does not need to know you.
• No scripts - Electrum-GRS does not download any script. A compromised server cannot send you arbitrary code and steal your groestlcoins.
• No single point of failure - The server code is open source, anyone can run a server.
• Transactions are signed locally - Your private keys are not shared with the server. You do not have to trust the server with your money.
• Firewall friendly - The client does not need to open a port, it simply polls the server for updates.
• Free software - Gnu GPL v3. Anyone can audit the code.
• Written in Python - The code is short, and easy to review.
• User Friendly - Support for Groestlcoin URIs, signed URIs and Groestlcoin aliases
• No Lock-In - You can export your private keys and use them in other groestlcoin clients.
• No Downtimes - Electrum-GRS servers are decentralized and redundant. Your wallet is never down.
• Proof Checking - Electrum-GRS Wallet verifies all the transactions in your history using SPV.
• Cold Storage - Keep your private keys offline, and go online with a watching-only wallet. Sign transactions from a computer that is always offline. Broadcast them from a machine that does not have your keys.
• Multisign - Split the permission to spend your coins between several wallets using parallel BIP32 derivations and P2SH addresses ("2 of 2", "2 of 3"). Compact serialization format for unsigned or partially signed transactions, that includes the BIP32 master public key and derivation needed to sign inputs. Serialized transactions can be sent to cosigners or to cold storage using QR codes

This application is licensed under the GPL version 3. There is no warranty and no party shall be made liable to you for damages. If you lose coins due to this app, no compensation will be given. Use this app solely at your own risk.

Important:
Store your secret phrase somewhere safe!
The multi-signature and non native segwit addresses starts with a "3" and not with a "F".
Electrum-GRS creates an encrypted filename default_wallet instead of wallet.dat (like in Groestlcoin Core)
• Location Windows: Navigate to C:\Users\USER NAME\AppData\Roaming\Electrum-grs\wallets (or open windows explorer and enter %appdata%\Electrum-grs\wallets) and back up your default_wallet file by making a copy of it and moving it to a secure location.
• Location Mac: Navigate to ~/Library/Application Support/Electrum-grs/wallets and back up your default_wallet file by making a copy of it and moving it to a secure location.

You can download it using the links below and be up and running with Groestlcoin in 5 minutes.

Download the OSX wallet here: https://github.com/Groestlcoin/electrum-grs/releases/download/v4.0.7/electrum-grs-4.0.7.dmg

Download Windows installer here: https://github.com/Groestlcoin/electrum-grs/releases/download/v4.0.7/electrum-grs-4.0.7-setup.exe
Download Windows standalone wallet here: https://github.com/Groestlcoin/electrum-grs/releases/download/v4.0.7/electrum-grs-4.0.7.exe
Download Windows portable version here: https://github.com/Groestlcoin/electrum-grs/releases/download/v4.0.7/electrum-grs-4.0.7-portable.exe
                                       
Download Linux installere here: https://github.com/Groestlcoin/electrum-grs/releases/download/v4.0.7/electrum-grs-4.0.7-x86_64.AppImage

Source code:
GitHub Source server: https://github.com/Groestlcoin/electrumx-grs
Github Source server installer: https://github.com/Groestlcoin/electrumx-grs-installer
Github Source client: https://github.com/Groestlcoin/electrum-grs

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v2.21.0 is now the official release version of Groestlcoin Core. On top of the new features, various bugfixes, updated translations and performance improvements. It is recommended to upgrade to this version as soon as possible.

Pool operators, P2Pool and solo miners especially because by default, Groestlcoin Core automatically set and unsets version bits as required.
The deployment sets the block version number to 0x20000004 between midnight 15th Dec 2020 and midnight 31th Dec 2021 to signal readiness for deployment. The version number consists of 0x20000000 to indicate version bits together with setting bit 2, shown as "taproot" in the "getblockchaininfo" RPC call. Please note it will keep generating blocks with version 0x20000004 until "taproot" is activated at which point is will automatically unset bit 2.

Taproot Upgrade Information
The taproot soft fork is fully backwards compatible with all Groestlcoin wallets, so you will continue to be able to safely send and receive groestlcoins whether or not taproot is activated.

Taproot softfork mainnet timeline:
• Signal: Miners will be able to signal that they are willing and able to enforce taproot starting at the beginning of the first 2016 block retarget period on or after 15 December 2020 (UTC). In short signalling started on block 3382848.
• Lock-in: Once 95% of blocks in a 2016 block long period have signaled that their miners are ready to enforce taproot then taproot will lock-in – meaning that unless the blockchain is rolled back at that point, taproot will become active.
• Activate: After another 2016 block period, taproot will activate, allowing miners to produce blocks containing taproot transactions on Groestlcoin’s mainnet. When taproot is activated, transaction-producing software will be able to enforce a new SegWit version 1 output type, with spending rules based on Taproot, Schnorr signatures, and Merkle branches.

Taproot softfork testnet timeline:
• Signal: Miners will be able to signal that they are willing and able to enforce taproot starting at the beginning of the first 2016 block retarget period on or after 15 December 2020 (UTC). In short signalling started on block 1929312.
• Lock-in: Once 75% of blocks in a 2016 block long period have signaled that their miners are ready to enforce taproot then taproot will lock-in – meaning that unless the blockchain is rolled back at that point, taproot will become active. In short Lock-in was on block 1931328.
• Activate: After another 2016 block period, taproot will activate, allowing miners to produce blocks containing taproot transactions on Groestlcoin’s testnet. In short Activate was on block 1933344. When taproot is activated, transaction-producing software will be able to enforce a new SegWit version 1 output type, with spending rules based on Taproot, Schnorr signatures, and Merkle branches.

What's new in version v2.21.0?
This is a major release of Groestlcoin Core with many protocol level improvements and code optimizations, featuring the technical equivalent of Bitcoin Core v0.21.0 but with Groestlcoin specific patches. On a general level, most of what is new is the second version bits BIP9 softfork deployment, the Schnorr Signatures for secp256k1, Taproot: SegWit version 1 spending rules and Validation of Taproot Scripts.

Changelog:
https://github.com/Groestlcoin/groestlcoin/blob/2.21.0/doc/release-notes/release-notes-2.21.0.md

The application may have unfound bugs and problems. Please report using the issue tracker at github:
https://github.com/groestlcoin/groestlcoin/issues

Important:
• There is no warranty and no party shall be made liable to you for damages. If you lose coins due to this app, no compensation will be given. Use this app solely at your own risk.
• Encrypt your wallet. This can be done by clicking the settings menu from inside the wallet. Make sure your password is secure and do not forget it.
• Make a copy your wallet.dat file as a backup and move it to a secure location:
Location Windows: Navigate to C:\Users\Username\AppData\Roaming\groestlcoin\wallet.dat (or open windows explorer and enter %appdata%\Groestlcoin\wallet.dat)
Location Mac: Finder -> Go {Hold Option] -> Library -> groestlcoin -> wallet.dat (~/Library/Application Support/groestlcoin/wallet.dat)

WARNING:
While this branch has been extensively tested to be compatible with the existing Groestlcoin v2.11.0, v2.13.3, v2.16.0, v2.16.3, v2.17.2, v2.18.2, v2.19.1 and v2.21.0 network there is the possibility that we missed something. ALWAYS BACKUP YOUR GROESTLCOIN WALLET BEFORE UPGRADING.

How to Upgrade?
Windows: If you are running an older version, shut it down. Wait until it has completely shut down (which might take a few minutes for older versions), then run the installer.
OSX: If you are running an older version, shut it down. Wait until it has completely shut down (which might take a few minutes for older versions), run the dmg and drag Groestlcoin Core to Applications. Users running macOS Catalina need to "right-click" and then choose "Open" to open the Groestlcoin Core .dmg.

Download the Windows Installer (64 bit) here: https://github.com/Groestlcoin/groestlcoin/releases/download/v2.21.0/groestlcoin-2.21.0-win64-setup-unsigned.exe
Download the Windows binaries (64 bit) here: https://github.com/Groestlcoin/groestlcoin/releases/download/v2.21.0/groestlcoin-2.21.0-win64.zip

Download the OSX Installer here: https://github.com/Groestlcoin/groestlcoin/releases/download/v2.21.0/groestlcoin-2.21.0-osx-unsigned.dmg
Download the OSX binaries here: https://github.com/Groestlcoin/groestlcoin/releases/download/v2.21.0/groestlcoin-2.21.0-osx64.tar.gz

Download the Linux binaries (64 bit) here: https://github.com/Groestlcoin/groestlcoin/releases/download/v2.21.0/groestlcoin-2.21.0-x86_64-linux-gnu.tar.gz
Download the ARM Linux binaries (64 bit) here: https://github.com/Groestlcoin/groestlcoin/releases/download/v2.21.0/groestlcoin-2.21.0-aarch64-linux-gnu.tar.gz
Download the ARM Linux binaries (32 bit) here: https://github.com/Groestlcoin/groestlcoin/releases/download/v2.21.0/groestlcoin-2.21.0-arm-linux-gnueabihf.tar.gz
Download the RISC-V Linux binaries (64 bit) here: https://github.com/Groestlcoin/groestlcoin/releases/download/v2.21.0/groestlcoin-2.21.0-riscv64-linux-gnu.tar.gz
Linux Snapcraft: https://snapcraft.io/groestlcoin-core
Linux Flathub: https://flathub.org/apps/details/org.groestlcoin.groestlcoin-qt
Linux Launchpad: https://launchpad.net/~groestlcoin/+archive/ubuntu/groestlcoin

Source code:
https://github.com/Groestlcoin/groestlcoin

https://stealthex.io/

Nina from StealthEX has asked me to post the new logo on our sites. I have trialled StealthEX, and liked it. Please feel free to review it yourself, and post the review here.

Grs Coin Analysis, Grs Chart 2020

https://bitcoinheat.com/2020/11/12/grs-coin-analysis-grs-coin-price-grs-chart-2020-groestl-value-groestlcoin-news/

Hello All,

I would like to ask that Unnamed Exchange, https://www.unnamed.exchange/, be considered for listing Groestl Coin.  This exchange has many features desirable for listing and is relatively inexpensive at only 0.05 BTC.

Cheers,
Waya

Gift cards from Groestlcoin have become available for residents of Ukraine for mutual settlements, payments for mobile operators and storage

https://www.groestlcoin.org/polispay-wallet/

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Groestlcoin users may find this tool helpful if they are trying to import watch-only wallets into software that expects a specific version of extended public key with regard to the paths used for key derivation.

Features
• Mainnet support for xpub, ypub, Ypub, zpub and Zpub
• Testnet support for tpub, upub, Upub, vpub and Vpub

Live version available at https://www.groestlcoin.org/xpub-converter/  But it is recommended to download Groestlcoin Extended Public Key Converter offline and run it on your pc. Open index.html to get started.

This application is licensed under MIT. There is no warranty and no party shall be made liable to you for damages. If you lose coins due to this app, no compensation will be given. Use this app solely at your own risk.

Download Seed Savior here: https://github.com/Groestlcoin/xpub-converter/archive/master.zip

Source code: https://github.com/Groestlcoin/xpub-converter

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Groestlcoin Spark is currently oriented for technically advanced users and is not an all-in-one package, but rather a "remote control" interface for a c-lightning node that has to be managed separately.
Groestlcoin Sparks supports sending and receiving payments, viewing history, and managing channels.
Groestlcoin Spark is a purely off-chain wallet, with no on-chain payments. This allows Groestlcoin Spark to fully realize the awesome UX enabled by lightning.
Groestlcoin Spark has a responsive UI suitable for mobile, tablet and desktop devices, but is best optimized for use on mobile

Changelog 0.2.16:
• Compatibility with c-lightning v0.9.0
• Support multi-part payments, grouped together in the UI
• Extract destination and description of outgoing payments from the BOLT11 request
• Fix bug in automatic credentials generation
• Properly handle outgoing payments without an associated requested amount
• Workaround for incorrect bolt11 string reported by c-lightning
• Fix the build script to properly install the client devDependencies
• Fix YAML rendering of payments with unknown destination/description. This bug only manifested when expert mode was enabled.

Features:
• Pay and Request are pretty intuitive and don't require much explaining. Try them!
• Display unit: Click the balance on the top-right or the unit in the "request payment" page to toggle the currency display unit. The available options are gro, groestls, milli, grs and usd.
• Theme switcher: Click the theme name on the bottom-right to change themes (you can choose between 16 bootswatch themes).
• Payment details: Click on payments in the list to display more details. (note that the fee shown includes c-lightning's overpayment randomization)
• Expert mode: Click the version number on the bottom-left to toggle expert mode. This will add two new menu items, "Logs" and "RPC Console", and display yaml dumps with additional information throughout the app.
• Node address: Click the node id on the footer to open the node info page which displays your node address (as text and QR).
• Channel management: Click the "Channels" button inside the node info page to show and manage channels.

This application is licensed under MIT. There is no warranty and no party shall be made liable to you for damages. If you lose coins due to this app, no compensation will be given. Use this app solely at your own risk.

Download link: https://play.google.com/store/apps/details?id=org.groestlcoin.spark

Source code: https://github.com/Groestlcoin/groestlcoin-spark/

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Groestlcoin Spark is currently oriented for technically advanced users and is not an all-in-one package, but rather a "remote control" interface for a c-lightning node that has to be managed separately.
Groestlcoin Sparks supports sending and receiving payments, viewing history, and managing channels.
Groestlcoin Spark is a purely off-chain wallet, with no on-chain payments. This allows Groestlcoin Spark to fully realize the awesome UX enabled by lightning.

Changelog 0.2.16:
• Compatibility with c-lightning v0.9.0
• Support multi-part payments, grouped together in the UI
• Extract destination and description of outgoing payments from the BOLT11 request
• Fix bug in automatic credentials generation
• Properly handle outgoing payments without an associated requested amount
• Workaround for incorrect bolt11 string reported by c-lightning
• Fix the build script to properly install the client devDependencies
• Fix YAML rendering of payments with unknown destination/description. This bug only manifested when expert mode was enabled.

Features:
• Pay and Request are pretty intuitive and don't require much explaining. Try them!
• Display unit: Click the balance on the top-right or the unit in the "request payment" page to toggle the currency display unit. The available options are gro, groestls, milli, grs and usd.
• Theme switcher: Click the theme name on the bottom-right to change themes (you can choose between 16 bootswatch themes).
• Payment details: Click on payments in the list to display more details. (note that the fee shown includes c-lightning's overpayment randomization)
• Expert mode: Click the version number on the bottom-left to toggle expert mode. This will add two new menu items, "Logs" and "RPC Console", and display yaml dumps with additional information throughout the app.
• Node address: Click the node id on the footer to open the node info page which displays your node address (as text and QR).
• Channel management: Click the "Channels" button inside the node info page to show and manage channels.

This application is licensed under MIT. There is no warranty and no party shall be made liable to you for damages. If you lose coins due to this app, no compensation will be given. Use this app solely at your own risk.

Download the OSX wallet here: https://github.com/Groestlcoin/groestlcoin-spark/releases/download/v0.2.16/groestlcoin-spark-0.2.16-mac.zip

Download Windows installer here: https://github.com/Groestlcoin/groestlcoin-spark/releases/download/v0.2.16/groestlcoin-spark-0.2.16-win-setup.exe
Download Windows portable version here: https://github.com/Groestlcoin/groestlcoin-spark/releases/download/v0.2.16/groestlcoin-spark-0.2.16-win-portable.exe
                                       
Download Linux Appimage installer here: https://github.com/Groestlcoin/groestlcoin-spark/releases/download/v0.2.16/groestlcoin-spark-0.2.16-linux-x86_64.AppImage
Download Linux Snap installer here: https://github.com/Groestlcoin/groestlcoin-spark/releases/download/v0.2.16/groestlcoin-spark-0.2.16-linux-amd64.snap
Download Linux Deb installer here: https://github.com/Groestlcoin/groestlcoin-spark/releases/download/v0.2.16/groestlcoin-spark-0.2.16-linux-amd64.deb

Source code: https://github.com/Groestlcoin/groestlcoin-spark/

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C-lightning is a lighweight, highly customizable and standard compliant implementation of the Lightning Network protocol.
C-lightning only works on Linux and Mac OS, and requires a locally (or remotely) running groestlcoind (version 2.16.0 or above) that is fully caught up with the network you're testing on.

Changelog 0.9.0
• We can now send multi-part payments as well as keysend spontaneous payments. This complements the support to receive these payments introduced in an earlier release. Large payments will now be split automatically into multiple parts that are more likely to succeed right away, and better protect your privacy. Should a payment not succeed at first we will adaptively split the amount and retry.
• We added support for watchtower plugins that help protect the node's funds while the node is not currently connected to the network.
• Support for optional fields in some messages has been removed, reducing complexity and replacing them with the more modern TLV extensions
• Splitting payments into smaller parts with MPP increases the traffic on the network and improves privacy by making payments look more homogenous. The added traffic provides cover for other payments.
• Extensible payment flow framework in libplugin allowing developers to write custom extensions without having to reinvent the wheel.
• Added RPC methods to create, sign and send PSBT transactions allowing c-lightning to be better integrated with wallets and higher-level protocols, such as coin-join and dual-funding.
• Added RPC methods to reserve and unreserve outputs controlled by the node to complement the PSBT support, for multi-step protocols.
• Added extensive accounting support in the form of the coin_movement hook that reports any change in the funds controlled by the node.
• Refactored the internals to use PSBT everywhere, leveraging libwally
• A number of new hooks and notifications were added to the plugin interface to allow deeper integration with c-lightning
• You are using a wallet that shows incorrect information due to missing fields in the RPC responses.
• Larger payments above 10,000 gros to non-public nodes fail due to the destination being unreachable.

Features
• Creating channels.
• Closing channels.
• Completely managing all channel states (including the exceptional ones!).
• Performing path finding within the network, passively forwarding incoming payments.
• Sending outgoing onion-encrypted payments through the network.
• Automatic channel management (autopilot).

This application is licensed under MIT. There is no warranty and no party shall be made liable to you for damages. If you lose coins due to this app, no compensation will be given. Use this app solely at your own risk.

Linux: https://github.com/Groestlcoin/lightning/blob/master/doc/INSTALL.md#to-build-on-ubuntu
OSX: https://github.com/Groestlcoin/lightning/blob/master/doc/INSTALL.md#to-build-on-macos

Source code: https://github.com/Groestlcoin/lightning

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GRSPay Testnet is a non-custodial invoicing system which eliminates the involvement of a third-party. Payments with GRSPay Testnet go directly to your wallet, which increases the privacy and security. Your private keys are never uploaded to the server. There is no address re-use, since each invoice generates a new address deriving from your tpubkey or vpubkey.

GRSPay Testnet is available at https://testnet.grspay.com/
https://www.youtube.com/watch?v=c7s3zZnlQ6M

https://www.youtube.com/watch?v=qNMTDEPhWhY

Changelog v1.0.5.5
• Payjoin support for stores (Receiving)
• Payjoin support in the internal wallet (Sending)
• Coin Selection feature in the internal wallet
• New invoice default theme
• New invoice dark theme
• New site default theme
• New site dark theme
• Camera QR Code scanner for Wallet
• Add Notifications feature
• Add Pull Payments feature
• Add Refund feature

Features
• Direct, P2P Groestlcoin Testnet payments
• Lightning Network Testnet support
• Complete control over private keys
• Enchanced privacy
• SegWit Testnet support
• Process payments for others
• Payment buttons
• Point of sale
• No transaction fees (other than those for the crypto networks)
• No processing fees
• No middleman
• No KYC
• The software is built in C#
• You can run GRSPay Testnet as a self-hosted solution on your own server or use a our host. The self-hosted solution allows you not only to attach an unlimited number of stores but also become the payment processor for others.
• Open Source - MIT license

This application is licensed under MIT. There is no warranty and no party shall be made liable to you for damages. If you lose coins due to this app, no compensation will be given. Use this app solely at your own risk.

Source code:
GRSPay: https://github.com/Groestlcoin/btcpayserver - GRSPay code

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GRSPay is a non-custodial invoicing system which eliminates the involvement of a third-party. Payments with GRSPay go directly to your wallet, which increases the privacy and security. Your private keys are never uploaded to the server. There is no address re-use, since each invoice generates a new address deriving from your xpubkey or zpubkey.

GRSPay is available at https://grspay.com
https://www.youtube.com/watch?v=c7s3zZnlQ6M

https://www.youtube.com/watch?v=qNMTDEPhWhY

Changelog v1.0.5.5
• Payjoin support for stores (Receiving)
• Payjoin support in the internal wallet (Sending)
• Coin Selection feature in the internal wallet
• New invoice default theme
• New invoice dark theme
• New site default theme
• New site dark theme
• Camera QR Code scanner for Wallet
• Add Notifications feature
• Add Pull Payments feature
• Add Refund feature

Features
• Direct, P2P Groestlcoin payments
• Lightning Network support
• Complete control over private keys
• Enchanced privacy
• SegWit support
• Process payments for others
• Easy-embeddable Payment buttons
• Point of sale app
• No transaction fees (other than those for the crypto networks)
• No processing fees
• No middleman
• No KYC
• The software is built in C#
• You can run GRSPay as a self-hosted solution on your own server or use a our host. The self-hosted solution allows you not only to attach an unlimited number of stores but also become the payment processor for others.
• Open Source - MIT license

This application is licensed under MIT. There is no warranty and no party shall be made liable to you for damages. If you lose coins due to this app, no compensation will be given. Use this app solely at your own risk.

Source code:
GRSPay: https://github.com/Groestlcoin/btcpayserver - GRSPay code

---

---

If you are an ordinary user of Groestlcoin and simply want the convenience of a web wallet with the security of a real application and support for multi-signature, then Elecrum-GRS is the right choice for you.

Changelog Electrum-GRS 4.0.2
• Lightning Network support (experimental)
• Our implementation of Lightning relies on Electrum-GRS servers to query channel states. Since servers can lie about the state of a channel, users should either use a server that they trust, or setup a private watchtower (see below). A watchtower is also recommended for lightning wallets that remain offline for extended periods of time (the default CSV 'to_self_delay' is 1 week). Please note that Electrum Personal Server (EPS) cannot be used with lightning wallets, because channels funding addresses are arbitrary.
• Lightning funds cannot be restored from seed. Instead, users need to create static backups of their channels. Static backups cannot be used to perform lightning transactions, they can only be used to trigger a remote-force-close of a channel.
• Lightning-enabled wallet files must not be copied. Instead, a backup of the wallet can be created from the Qt menu, and it will contain static backups of all its channels. Backups can also be exported for each channel (e.g. via QR code), and imported in another wallet. Since backups are encrypted with a key derived from the wallet's xpub, they can only be imported into another instance of the same wallet, or a watch-only version of it. The force-close is not triggered automatically when the backup is imported; imported backups can live inside a wallet file.
• Lightning can be enabled in the GUI (Wallet>Information) or from the CLI (init_lightning). Lightning is currently restricted to HD p2wpkh wallets (including watch-only and hardware wallets). The Qt GUI, CLI/RPC, and the kivy GUI (Android) all have LN support, with feature-richness in that order.
• LN protocol details: dataloss_protect and static_remotekey are required; varonion and payment_secret are implemented, MPP not yet. Channels are not announced ('private'), forwarding is disabled. We do not serve gossip queries, only consume them.
• Submarine swaps: the GUI integrates a service that offers atomically exchanging on-chain and lightning groestlcoins for a fee. Groestlcoin development team runs a central server for this, powered by the Boltz backend.
• Watchtowers: Electrum-GRS can run a local watchtower (GUI setting), or it can connect to a remote watchtower. A watchtower contains pre-signed transactions and does not need your private keys. A local watchtower will watch your channels whenever an Electrum-GRS instance is running, without needing access to your wallet file. An Electrum-GRS daemon can be configured to be used as a remote watchtower by setting 'watchtower_address', 'watchtower_user' and 'watchtower_password'.
• Partially Signed Bitcoin Transactions (PSBT, BIP-174) are supported. The previous Electrum-GRS partial transaction format is no longer supported, i.e. this is an incompatible change. Users should make sure that all instances of Electrum-GRS they use to co-sign or offline sign, are updated together.
• Compatibility with latest Trezor fw
• Libsecp256k1 is now required (previously optional). python-ecdsa remains a dependency but it is now only used for DNSSEC.
• Added: either one of pycryptodomex or cryptography is now required, mainly due to LN (previously pycryptodomex was optional, for fast AES)
• Removed: jsonrpclib-pelix, the JSON-RPC library used for CLI/daemon
• Separation between output selection and transaction finalization.
• Coin selection moved to the Coins tab, and it affects all txns, e.g. RBF fee-bumping, LN channel opens, submarine swaps.
• Editable tx preview dialog that allows e.g. changing the locktime, toggling RBF, and manual coinjoins.
• HTTP PayServer: The configuration of a groestlcoin-accepting website using Electrum-GRS has been simplified and requires fewer steps (see documentation). The Payserver supports BIP70 and Lightning payments.
• The API of several CLI/RPC commands have changed, and several new commands have been introduced (mainly for LN).
• The .tar.gz source dist is now built reproducibly. Relatedly, we no longer distribute a .zip sdist.
• We now grind low R for ECDSA signatures to match groestlcoind
• Lots and lots of other minor bugfixes and improvements.
• We now build two APKs, one for ARMv7 and one for ARMv8
• The kivy GUI now supports importing BIP39 seeds
• Each wallet on kivy now can have a separate generic password, using which the wallet files are encrypted. An optional PIN, shared among all wallets, can be added to get prompted for spends.

Features
• Encrypted wallet - the file that contains your groestlcoins is protected with a password. You are protected from thieves.
• Deterministic key generation - If you lose your wallet, you can recover it from its seed. You are protected from your own mistakes.
• Instant on - the client does not download the blockchain, it requests that information from a server. No delays, always up-to-date.
• Freedom and Privacy - The server does not store user accounts. You are not tied to a particular server, and the server does not need to know you.
• No scripts - Electrum-GRS does not download any script. A compromised server cannot send you arbitrary code and steal your groestlcoins.
• No single point of failure - The server code is open source, anyone can run a server.
• Transactions are signed locally - Your private keys are not shared with the server. You do not have to trust the server with your money.
• Firewall friendly - The client does not need to open a port, it simply polls the server for updates.
• Free software - Gnu GPL v3. Anyone can audit the code.
• Written in Python - The code is short, and easy to review.
• User Friendly - Support for Groestlcoin URIs, signed URIs and Groestlcoin aliases
• No Lock-In - You can export your private keys and use them in other groestlcoin clients.
• No Downtimes - Electrum-GRS servers are decentralized and redundant. Your wallet is never down.
• Proof Checking - Electrum-GRS Wallet verifies all the transactions in your history using SPV.
• Cold Storage - Keep your private keys offline, and go online with a watching-only wallet. Sign transactions from a computer that is always offline. Broadcast them from a machine that does not have your keys.
• Multisign - Split the permission to spend your coins between several wallets using parallel BIP32 derivations and P2SH addresses ("2 of 2", "2 of 3"). Compact serialization format for unsigned or partially signed transactions, that includes the BIP32 master public key and derivation needed to sign inputs. Serialized transactions can be sent to cosigners or to cold storage using QR codes

This application is licensed under the GPL version 3. There is no warranty and no party shall be made liable to you for damages. If you lose coins due to this app, no compensation will be given. Use this app solely at your own risk.

Important:
Store your secret phrase somewhere safe!
The multi-signature and non native segwit addresses starts with a "3" and not with a "F".

Electrum-GRS is available in the Google play store:
https://play.google.com/store/apps/details?id=org.groestlcoin.electrumgrs

Source code:
GitHub Source server: https://github.com/Groestlcoin/electrumx-grs
Github Source server installer: https://github.com/Groestlcoin/electrumx-grs-installer
Github Source client: https://github.com/Groestlcoin/electrum-grs

---

---

If you are an ordinary user of Groestlcoin and simply want the convenience of a web wallet with the security of a real application and support for multi-signature, then Elecrum-GRS is the right choice for you.

Changelog Electrum-GRS 4.0.2
• Lightning Network support (experimental)
• Our implementation of Lightning relies on Electrum-GRS servers to query channel states. Since servers can lie about the state of a channel, users should either use a server that they trust, or setup a private watchtower (see below). A watchtower is also recommended for lightning wallets that remain offline for extended periods of time (the default CSV 'to_self_delay' is 1 week). Please note that Electrum Personal Server (EPS) cannot be used with lightning wallets, because channels funding addresses are arbitrary.
• Lightning funds cannot be restored from seed. Instead, users need to create static backups of their channels. Static backups cannot be used to perform lightning transactions, they can only be used to trigger a remote-force-close of a channel.
• Lightning-enabled wallet files must not be copied. Instead, a backup of the wallet can be created from the Qt menu, and it will contain static backups of all its channels. Backups can also be exported for each channel (e.g. via QR code), and imported in another wallet. Since backups are encrypted with a key derived from the wallet's xpub, they can only be imported into another instance of the same wallet, or a watch-only version of it. The force-close is not triggered automatically when the backup is imported; imported backups can live inside a wallet file.
• Lightning can be enabled in the GUI (Wallet>Information) or from the CLI (init_lightning). Lightning is currently restricted to HD p2wpkh wallets (including watch-only and hardware wallets). The Qt GUI, CLI/RPC, and the kivy GUI (Android) all have LN support, with feature-richness in that order.
• LN protocol details: dataloss_protect and static_remotekey are required; varonion and payment_secret are implemented, MPP not yet. Channels are not announced ('private'), forwarding is disabled. We do not serve gossip queries, only consume them.
• Submarine swaps: the GUI integrates a service that offers atomically exchanging on-chain and lightning groestlcoins for a fee. Groestlcoin development team runs a central server for this, powered by the Boltz backend.
• Watchtowers: Electrum-GRS can run a local watchtower (GUI setting), or it can connect to a remote watchtower. A watchtower contains pre-signed transactions and does not need your private keys. A local watchtower will watch your channels whenever an Electrum-GRS instance is running, without needing access to your wallet file. An Electrum-GRS daemon can be configured to be used as a remote watchtower by setting 'watchtower_address', 'watchtower_user' and 'watchtower_password'.
• Partially Signed Bitcoin Transactions (PSBT, BIP-174) are supported. The previous Electrum-GRS partial transaction format is no longer supported, i.e. this is an incompatible change. Users should make sure that all instances of Electrum-GRS they use to co-sign or offline sign, are updated together.
• Compatibility with latest Trezor fw
• Libsecp256k1 is now required (previously optional). python-ecdsa remains a dependency but it is now only used for DNSSEC.
• Added: either one of pycryptodomex or cryptography is now required, mainly due to LN (previously pycryptodomex was optional, for fast AES)
• Removed: jsonrpclib-pelix, the JSON-RPC library used for CLI/daemon
• Separation between output selection and transaction finalization.
• Coin selection moved to the Coins tab, and it affects all txns, e.g. RBF fee-bumping, LN channel opens, submarine swaps.
• Editable tx preview dialog that allows e.g. changing the locktime, toggling RBF, and manual coinjoins.
• HTTP PayServer: The configuration of a groestlcoin-accepting website using Electrum-GRS has been simplified and requires fewer steps (see documentation). The Payserver supports BIP70 and Lightning payments.
• The API of several CLI/RPC commands have changed, and several new commands have been introduced (mainly for LN).
• The .tar.gz source dist is now built reproducibly. Relatedly, we no longer distribute a .zip sdist.
• We now grind low R for ECDSA signatures to match groestlcoind
• Lots and lots of other minor bugfixes and improvements.
• We now build two APKs, one for ARMv7 and one for ARMv8
• The kivy GUI now supports importing BIP39 seeds
• Each wallet on kivy now can have a separate generic password, using which the wallet files are encrypted. An optional PIN, shared among all wallets, can be added to get prompted for spends.

Features
• Encrypted wallet - the file that contains your groestlcoins is protected with a password. You are protected from thieves.
• Deterministic key generation - If you lose your wallet, you can recover it from its seed. You are protected from your own mistakes.
• Instant on - the client does not download the blockchain, it requests that information from a server. No delays, always up-to-date.
• Freedom and Privacy - The server does not store user accounts. You are not tied to a particular server, and the server does not need to know you.
• No scripts - Electrum-GRS does not download any script. A compromised server cannot send you arbitrary code and steal your groestlcoins.
• No single point of failure - The server code is open source, anyone can run a server.
• Transactions are signed locally - Your private keys are not shared with the server. You do not have to trust the server with your money.
• Firewall friendly - The client does not need to open a port, it simply polls the server for updates.
• Free software - Gnu GPL v3. Anyone can audit the code.
• Written in Python - The code is short, and easy to review.
• User Friendly - Support for Groestlcoin URIs, signed URIs and Groestlcoin aliases
• No Lock-In - You can export your private keys and use them in other groestlcoin clients.
• No Downtimes - Electrum-GRS servers are decentralized and redundant. Your wallet is never down.
• Proof Checking - Electrum-GRS Wallet verifies all the transactions in your history using SPV.
• Cold Storage - Keep your private keys offline, and go online with a watching-only wallet. Sign transactions from a computer that is always offline. Broadcast them from a machine that does not have your keys.
• Multisign - Split the permission to spend your coins between several wallets using parallel BIP32 derivations and P2SH addresses ("2 of 2", "2 of 3"). Compact serialization format for unsigned or partially signed transactions, that includes the BIP32 master public key and derivation needed to sign inputs. Serialized transactions can be sent to cosigners or to cold storage using QR codes

This application is licensed under the GPL version 3. There is no warranty and no party shall be made liable to you for damages. If you lose coins due to this app, no compensation will be given. Use this app solely at your own risk.

Important:
Store your secret phrase somewhere safe!
The multi-signature and non native segwit addresses starts with a "3" and not with a "F".
Electrum-GRS creates an encrypted filename default_wallet instead of wallet.dat (like in Groestlcoin Core)
• Location Windows: Navigate to C:\Users\USER NAME\AppData\Roaming\Electrum-grs\wallets (or open windows explorer and enter %appdata%\Electrum-grs\wallets) and back up your default_wallet file by making a copy of it and moving it to a secure location.
• Location Mac: Navigate to ~/Library/Application Support/Electrum-grs/wallets and back up your default_wallet file by making a copy of it and moving it to a secure location.

You can download it using the links below and be up and running with Groestlcoin in 5 minutes.

Download the OSX wallet here: https://github.com/Groestlcoin/electrum-grs/releases/download/v4.0.2/electrum-grs-4.0.2.dmg

Download Windows installer here: https://github.com/Groestlcoin/electrum-grs/releases/download/v4.0.2/electrum-grs-4.0.2-setup.exe
Download Windows standalone wallet here: https://github.com/Groestlcoin/electrum-grs/releases/download/v4.0.2/electrum-grs-4.0.2.exe
Download Windows portable version here: https://github.com/Groestlcoin/electrum-grs/releases/download/v4.0.2/electrum-grs-4.0.2-portable.exe
                                       
Download Linux installere here: https://github.com/Groestlcoin/electrum-grs/releases/download/v4.0.2/electrum-grs-4.0.2-x86_64.AppImage

Source code:
GitHub Source server: https://github.com/Groestlcoin/electrumx-grs
Github Source server installer: https://github.com/Groestlcoin/electrumx-grs-installer
Github Source client: https://github.com/Groestlcoin/electrum-grs

---

---

v2.20.1 is now the official release version of Groestlcoin Core. On top of the new features, various bugfixes, updated translations and performance improvements. It is recommended to upgrade to this version as soon as possible.

What's new in version v2.20.1?
This is a major release of Groestlcoin Core with many protocol level improvements and code optimizations, featuring the technical equivalent of Bitcoin Core v0.20.1 but with Groestlcoin specific patches.

Changelog:
https://github.com/Groestlcoin/groestlcoin/blob/2.20.1/doc/release-notes/release-notes-2.20.1.md

The application may have unfound bugs and problems. Please report using the issue tracker at github:
https://github.com/groestlcoin/groestlcoin/issues

Important:
• There is no warranty and no party shall be made liable to you for damages. If you lose coins due to this app, no compensation will be given. Use this app solely at your own risk.
• Encrypt your wallet. This can be done by clicking the settings menu from inside the wallet. Make sure your password is secure and do not forget it.
• Make a copy your wallet.dat file as a backup and move it to a secure location:
Location Windows: Navigate to C:\Users\Username\AppData\Roaming\groestlcoin\wallet.dat (or open windows explorer and enter %appdata%\Groestlcoin\wallet.dat)
Location Mac: Finder -> Go {Hold Option] -> Library -> groestlcoin -> wallet.dat (~/Library/Application Support/groestlcoin/wallet.dat)

WARNING:
While this branch has been extensively tested to be compatible with the existing Groestlcoin v2.11.0, v2.13.3, v2.16.0, v2.16.3, v2.17.2, v2.18.2 and v2.19.1 network there is the possibility that we missed something. ALWAYS BACKUP YOUR GROESTLCOIN WALLET BEFORE UPGRADING.

How to Upgrade?
Windows: If you are running an older version, shut it down. Wait until it has completely shut down (which might take a few minutes for older versions), then run the installer.
OSX: If you are running an older version, shut it down. Wait until it has completely shut down (which might take a few minutes for older versions), run the dmg and drag Groestlcoin Core to Applications. Users running macOS Catalina need to "right-click" and then choose "Open" to open the Groestlcoin Core .dmg.

Download the Windows Installer (64 bit) here: https://github.com/Groestlcoin/groestlcoin/releases/download/v2.20.1/groestlcoin-2.20.1-win64-setup-unsigned.exe
Download the Windows binaries (64 bit) here: https://github.com/Groestlcoin/groestlcoin/releases/download/v2.20.1/groestlcoin-2.20.1-win64.zip

Download the OSX Installer here: https://github.com/Groestlcoin/groestlcoin/releases/download/v2.20.1/groestlcoin-2.20.1-osx-unsigned.dmg
Download the OSX binaries here: https://github.com/Groestlcoin/groestlcoin/releases/download/v2.20.1/groestlcoin-2.20.1-osx64.tar.gz

Download the Linux binaries (64 bit) here: https://github.com/Groestlcoin/groestlcoin/releases/download/v2.20.1/groestlcoin-2.20.1-x86_64-linux-gnu.tar.gz
Download the ARM Linux binaries (64 bit) here: https://github.com/Groestlcoin/groestlcoin/releases/download/v2.20.1/groestlcoin-2.20.1-aarch64-linux-gnu.tar.gz
Download the ARM Linux binaries (32 bit) here: https://github.com/Groestlcoin/groestlcoin/releases/download/v2.20.1/groestlcoin-2.20.1-arm-linux-gnueabihf.tar.gz
Download the RISC-V Linux binaries (64 bit) here: https://github.com/Groestlcoin/groestlcoin/releases/download/v2.20.1/groestlcoin-2.20.1-riscv64-linux-gnu.tar.gz
Linux Snapcraft: https://snapcraft.io/groestlcoin-core
Linux Flathub: https://flathub.org/apps/details/org.groestlcoin.groestlcoin-qt
Linux Launchpad: https://launchpad.net/~groestlcoin/+archive/ubuntu/groestlcoin

Source code:
https://github.com/Groestlcoin/groestlcoin

Bithumb Global has announced the listing of Groestlcoin, GRS token will be added on August 6, and trading will begin on August 7, GRS / USDT pair https://support.bithumb.pro/hc/en-us/articles/360052597813/

Listing on WazirX
https://coindar.org/en/event/groestlcoin-grs-listing-on-wazirx-29577

---

---

v2.19.1 is now the official release version of Groestlcoin Core. On top of the new features, various bugfixes, updated translations and performance improvements. It is recommended to upgrade to this version as soon as possible.

What's new in version v2.19.1?
This is a major release of Groestlcoin Core with many protocol level improvements and code optimizations, featuring the technical equivalent of Bitcoin Core v0.19.1 but with Groestlcoin specific patches.

Changelog:
https://github.com/Groestlcoin/groestlcoin/blob/2.19.1/doc/release-notes/release-notes-2.19.1.md

The application may have unfound bugs and problems. Please report using the issue tracker at github:
https://github.com/groestlcoin/groestlcoin/issues

Important:
• There is no warranty and no party shall be made liable to you for damages. If you lose coins due to this app, no compensation will be given. Use this app solely at your own risk.
• Encrypt your wallet. This can be done by clicking the settings menu from inside the wallet. Make sure your password is secure and do not forget it.
• Make a copy your wallet.dat file as a backup and move it to a secure location:
Location Windows: Navigate to C:\Users\Username\AppData\Roaming\groestlcoin\wallet.dat (or open windows explorer and enter %appdata%\Groestlcoin\wallet.dat)
Location Mac: Finder -> Go {Hold Option] -> Library -> groestlcoin -> wallet.dat (~/Library/Application Support/groestlcoin/wallet.dat)

WARNING:
While this branch has been extensively tested to be compatible with the existing Groestlcoin v2.11.0, v2.13.3, v2.16.0, v2.16.3, v2.17.2 and v2.18.2 network there is the possibility that we missed something. ALWAYS BACKUP YOUR GROESTLCOIN WALLET BEFORE UPGRADING.

How to Upgrade?
Windows: If you are running an older version, shut it down. Wait until it has completely shut down (which might take a few minutes for older versions), then run the installer.
OSX: If you are running an older version, shut it down. Wait until it has completely shut down (which might take a few minutes for older versions), run the dmg and drag Groestlcoin Core to Applications. Users running macOS Catalina need to "right-click" and then choose "Open" to open the Groestlcoin Core .dmg.

Download the Windows Installer (64 bit) here: https://github.com/Groestlcoin/groestlcoin/releases/download/v2.19.1/groestlcoin-2.19.1-win64-setup-unsigned.exe
Download the Windows binaries (64 bit) here: https://github.com/Groestlcoin/groestlcoin/releases/download/v2.19.1/groestlcoin-2.19.1-win64.zip

Download the OSX Installer here: https://github.com/Groestlcoin/groestlcoin/releases/download/v2.19.1/groestlcoin-2.19.1-osx-unsigned.dmg
Download the OSX binaries here: https://github.com/Groestlcoin/groestlcoin/releases/download/v2.19.1/groestlcoin-2.19.1-osx64.tar.gz

Download the Linux binaries (64 bit) here: https://github.com/Groestlcoin/groestlcoin/releases/download/v2.19.1/groestlcoin-2.19.1-x86_64-linux-gnu.tar.gz
Download the Linux binaries (32 bit) here: https://github.com/Groestlcoin/groestlcoin/releases/download/v2.19.1/groestlcoin-2.19.1-i686-pc-linux-gnu.tar.gz
Download the ARM Linux binaries (64 bit) here: https://github.com/Groestlcoin/groestlcoin/releases/download/v2.19.1/groestlcoin-2.19.1-aarch64-linux-gnu.tar.gz
Download the ARM Linux binaries (32 bit) here: https://github.com/Groestlcoin/groestlcoin/releases/download/v2.19.1/groestlcoin-2.19.1-arm-linux-gnueabihf.tar.gz
Linux Snapcraft: https://snapcraft.io/groestlcoin-core
Linux Flathub: https://flathub.org/apps/details/org.groestlcoin.groestlcoin-qt
Linux Launchpad: https://launchpad.net/~groestlcoin/+archive/ubuntu/groestlcoin

Source code:
https://github.com/Groestlcoin/groestlcoin

---

---

Groestlcoin Spark is currently oriented for technically advanced users and is not an all-in-one package, but rather a "remote control" interface for a c-lightning node that has to be managed separately.
Groestlcoin Sparks supports sending and receiving payments, viewing history, and managing channels.
Groestlcoin Spark is a purely off-chain wallet, with no on-chain payments. This allows Groestlcoin Spark to fully realize the awesome UX enabled by lightning.
Groestlcoin Spark has a responsive UI suitable for mobile, tablet and desktop devices, but is best optimized for use on mobile

Changelog 0.2.14:
• Fix bug with missing channel reserve
• Fix channels view
• Detect if the "base directory" is provided and default to the groestlcoin mainnet network subdirectory within in.
• Don't display unconfirmed onchain balance
• Fix: Some QR codes not read properly in the web QR scanner
• Fix: Resolve TLS issues with NodeJS 10
• Electron: Update to v8
• Fix bug in automatic credentials generation
• Fix Android crashes caused by plugin-local-notifications
• Cordova Android: Allow connecting to server in cleartext

Features:
• Pay and Request are pretty intuitive and don't require much explaining. Try them!
• Display unit: Click the balance on the top-right or the unit in the "request payment" page to toggle the currency display unit. The available options are gro, groestls, milli, grs and usd.
• Theme switcher: Click the theme name on the bottom-right to change themes (you can choose between 16 bootswatch themes).
• Payment details: Click on payments in the list to display more details. (note that the fee shown includes c-lightning's overpayment randomization)
• Expert mode: Click the version number on the bottom-left to toggle expert mode. This will add two new menu items, "Logs" and "RPC Console", and display yaml dumps with additional information throughout the app.
• Node address: Click the node id on the footer to open the node info page which displays your node address (as text and QR).
• Channel management: Click the "Channels" button inside the node info page to show and manage channels.

This application is licensed under MIT. There is no warranty and no party shall be made liable to you for damages. If you lose coins due to this app, no compensation will be given. Use this app solely at your own risk.

Download link: https://play.google.com/store/apps/details?id=org.groestlcoin.spark

Source code: https://github.com/Groestlcoin/groestlcoin-spark/