When you choose a key for signing your APK for publishing in GooglePlay, you need to care of this key for the next 25 years if you want to do updates.
- The key should not be shared with anyone.
- The key should not be lost.
If you do several games, you face the question of having your key
DeveloperName and sign all games with it, or have multiple keys like
DeveloperName_GameOne for one game,
DeveloperName_GameTwo for another, and so on.
Google says here http://developer.android.com/intl/es/tools/publishing/app-signing.html that if you sign several APPs with the same key, they may talk to each other. So it seems that having all with one key will allow future interoperability between games easier.
Instead, if at some point someone wants to buy you one of your games, but not the other, you don't want to give the keys to the non-sold games but still you don't want the buyer to break the update-flow. So it seems that having each game with a different key is better.
What exact benefeits will one have if one signs 2 games with the same key? Is that necessary? Is that worth for future interop between games?
What is the correct practice for an indie doing several games regarding the signature of them?