blockage and csmcanarney are right, but let me expand a little on what we're building with vault (which is coming together, but still 1-2 months from production quality).
Vault Value proposition for users:
* A highly usable web-wallet, suitable for day-to-day use with all the features you'd expect for that
* We don't ask who you are, or why you're using vault
* Good (external) privacy, your coins are mixed with everyones coins
* Offchain transfers: Transfer money to people/accounts instantly off-chain.
* Unified login system for gambling sites. Vault is an OAuth2 provider, and you can authorize apps to login and have access up to a specified amount of money. Not only do you get the unified identity across sites, but you can "Add funds" instantly by just authorizing the app to gamble/spend more (no more waiting for confirmations)
Vault Value proposition for investors:
* Invest your money in a single bankroll, that is used by multiple websites. You only need to trust Vault, and not other gambling operators.
Vault Value proposition for devs/casinos:
* Focus only on building an engaging gambling game. You can even build a gambling game without running your own server!
* Leverage the dirt simple "Login With Vault", no screwing around with creating your own user system, security system, 2FA, forgot password, support requests to reset passwords/emails/2FA, etc., handling withdrawals, deposits and reduce friction for people who already have a vault account
* You can use the flexible provably fair betting API to make bets on behalf of your user. You can verify them in real time, to make sure Vault isn't ripping you off. The provably fair betting API is flexible enough to support games like: dice, roulette, plinko and slots from day one.
* Have users gamble directly against Vault's bankroll. This means on *day 1* you can offer high limits, and have absolutely no worries about variance or solvency, vault takes care of that for you.
* Offload security to Vault. All users balances are kept in vault as is the site bankroll.
* Have a steady source of income. From investors perspective, we always give them a 1/2 kelly for every bet (with a minimum of a 0.1% house edge). When ever you send Vault a bet with a house-edge greater than a 1/2 kelly, vault and your app will a 50-50 profit share. [1]. The core principle here, you get a steady stream of income based on your volume and the odds you offer your users.
[1] Details of the investor/vault/app profit sharing subject to change
I see you are making huge developments. This can change the gambling sites forever... Please keep on improving these ideas, they will be greatly appreciated!