Please select at least one of the signature versions to use in Android Studio 2.3
Now while generating a signed APK in Android Studio, it\'s showing
According to this link: signature help
APK Signature Scheme v2 offers:
Android 7.0 introduces APK Signature Scheme v2, a new app-signing scheme that offers faster app install times and more protection against unauthorized alterations to APK files. By default, Android Studio 2.2 and the Android Plugin for Gradle 2.2 sign your app using both APK Signature Scheme v2 and the traditional signing scheme, which uses JAR signing.
It is recommended to use APK Signature Scheme v2 but is not mandatory.
Although we recommend applying APK Signature Scheme v2 to your app, this new scheme is not mandatory. If your app doesn't build properly when using APK Signature Scheme v2, you can disable the new scheme.