I have played the android app ever since it came out, every .apk has worked fine. I stopped at 0.923 for a while since there was a string of buggy releases and I didn't want to screw up my saves (since saving to file in the app is apparently broken. it works for some people, but not for others, including me.) However when attempting to update from 0.923 to 0.928, something I've done many times before on every other version, the app fails to install with a "failed to install" message. This is obviously very uninformative, but my guess would be that either the signature is wrong so the app won't accept the new version as a legitimate update, or it's built for the wrong architecture, or something else. Every other version up to 0.23 worked fine.