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I have developed an Android app (Phonegap) in Eclipse with signed key APK file version (1.0.0) and save it on SD card of phone or download from site.
I am able to install it on non-rooted Samsung Galaxy Tab 2 phone having enabled "Unknown sources" and also able to update app with same signed key APK file version (2.0.0). It's successfully installed and working fine.
But now when I am going to install older signed version (1.0.0) app over latest version (2.0.0) by choosing "Install", I'm getting "App not installed message".
App downgrade working fine on Micromax Canvas device but not in Tab 2.
How to install it?