"Application not installed" when APK is not signed
I wanted to test a small android app which I was working on, on my phone. I had already tested this app on an emulator and even on a physical device - my phone earlier, but I had done that via ADB. However, I wanted to install it this time from the apk file. Now, when I ran gradlew assembleRelease there were 2 apk files generated in the projectname /build/apk directory. One named projectname -debug-unaligned.apk and the other named projectname -release-unsigned.apk . The release unsigned one seemed to be the right one to try out. So I tried installing it on my phone. Everything went on well until I saw a message when it had just seemed like the app was installed which actually read: "Application not installed". I was a bit confused looking at the message, I didn't quite understand what went wrong as there was no details as to what went wrong in the message. I had pretty much everything configured the way I thought would be required like checking off the box against ...