I have made two versions of my application, a “large” version, and a “mini”/”lite” version.
Should I be signing both of these with the same key? Or should I sign with a unique key for each of them?
What are the repercussions of signing multiple applications with the same key?
Signing is used mainly to identify an application’s developer. If anything, you’re suppose to sign all applications you make with the same key.
Read everything here:
http://developer.android.com/guide/publishing/app-signing.html