The same issue was posted here but the answer given didn\'t work for me. I\'ve uploaded to the store before and now I can\'t update my app to include some bug fixes. Wheneve
Google Play will not accept a debug version of your .apk file. You can only upload an .apk compiled as release version. Additionally it must be signed with your Android Developer key, which happens in the same step, at least if you're using Eclipse.
Make sure you distribute an .apk file which is your Signed Release version, as described here:
http://developer.android.com/tools/publishing/app-signing.html#releasecompile