BitcoinSpinner uses private app storage, which is wiped at uninstall. However, this also has the nice feature that other apps cannot get to it, which is paramount. Another nice thing is that BitcoinSpinner only needs network access privileges. This lets you know that it does not try to snag your address book or keys from other apps using SD card storage.
In the Linode security breach trust given to their proprietary infrastructure was violated and bitcoins were stolen.
I'm wondering if there is a similar vulnerability with a mobile platform. I read in the Android how-to for publishing an app that only an app signed with your private release key will get pushed out as an update. What if, however, your system used for building was compromised and an attacker were to get your private release keys to build a rogue update (that stole bitcoin private keys). If that roge release were published to the marketplace nobody would likely notice a problem until after the attacker already would have a lot of private keys!
If I were storing an amount of bitcoins worth worrying about, I might then want a way to disable the automatic update of this app. Is that possible?
Also, might there be an announcement here for when you publish, maybe signed with your PGP key, which includes a signature for the release to be published to the Android Market?
I know this sounds paranoid, but crazier things have happened before, right?
These are all valid concerns. Hacking bitcoin related services has turned out to be quite profitable.
Android apps are not automatically updated by default. This is an option that you can enable on your device, but I recommend that you don't.
Whenever I update BitcoinSpinner I announce it in this thread:
https://bitcointalksearch.org/topic/bitcoinspinner-53353However publishing a signature on the APK with a different key doesn't give you much, as you (as far as I know) cannot retrieve a hash of the application from the Android Market. If you are really paranoid you should download the sources and roll your own. This also allows you to review any changes that have been added since last release.
(By the way, there is an update in the pipe which adds an address book and launching the send page from a Bitcoin URL)