Automatically rename your APKs

This will result in an APK named com.androidgradle.demo-1.0.1.apk instead of app-debug.apk

android {
   compileSdkVersion 21
   buildToolsVersion "23.0.2"

    defaultConfig {
        applicationId "com.androidgradle.demo"
        minSdkVersion 17
        targetSdkVersion 24
        versionCode 1
        versionName "1.0.1"
    }
  ...

 android.applicationVariants.all {
        variant ->  variant.outputs.each {
            output ->
                def file = output.outputFile
                output.outputFile = new File(file.parent, "${variant.applicationId}-${variant.versionName}.apk")
        }
    }

 ...
}