After upgrading to android studio 3.0 the debug apk is saying App not istalled.
The package appears to be corrupted
Looks like we can not directly use the apk after running on the device from the build->output->apk folder.
After upgrading to android studio 3.0 you need to go to Build -> Build Apk(s) then copy the apk from build -> output -> apk -> debug
Like this -