Uninstall the Debug APK Before Trying the Release APK
SummaryWhen you switch your Android app from debug mode to release mode, you may find that the release mode APK file won't install. The trick is to uninstall the debug mode .apk file before installing the release mode .apk file.
DetailsWhen you normally build an Android app, it is built in debug mode and signed with a debug key. This app is testable but can't be distributed in the Android Marketplace. If you install this app on your phone for testing, things will go fine, until you make the release build for release. When you go to install that .apk file, it will refuse to install.
You must first uninstall the debug mode app. On the home screen, press the menu button to get Settings. Then go to Applications/Manage applications. Click on your app, and finally click "Uninstall". You will now be able to install your release-mode application without any trouble.
Copyright © 2016 Andrew Oliver