The Android Application Generator (BBC2APK) has been updated to version 1.12 in order to be compatible with BBCSDL v1.34a. The main reason for the update being necessary is that the Android edition of v1.34a uses Version 2 of the signing algorithm whereas earlier releases used only Version 1. To make a valid APK BBC2APK has to do the same.
If you use BBC2APK you should download the latest version and update the APK template it uses (click on the Download button). That should ensure that any APKs you build install successfully. If you encounter any problems let me know.