Two engineers are working on an android project. To publish the apk (not on Playstore, but private publication), they each run their project and then get the resulting apk and then publish. As it turns out a user cannot simply update between the apks produced from the two different computers. If a user's current apk was published by developer Zack; to update to the latest version, which happen to come from developer Max, the user must in fact delete and reinstall. How do I resolve this problem? I was hoping to find whatever key is used on one of the computers and pass it to the other developer. But I can't find where the keys are stored.
Naturally, I would use Android Tools > Export Signed Application Package to publish. But the present situation is as above. How do I fix that problem without having user's continuously deleting or -- on the other hand -- restrict publication to one machine?