Session 'app': Error Launching activity

Question

After the Android Studio 2.0 update while the gradle build finishes I get this :

Session \'app\': Error Launching activity .

It prevents the app from starting

Answer 1

I got the same error. This issue was caused by uninstalling the app from the device (uninstalled from only 1 user)

Solved by logging into the other user and uninstall the app from there.

and it solved.