Sample of using productFlavours.

build.gradle

apply plugin: 'com.android.application'

android {
    compileSdkVersion 23
    buildToolsVersion "23.0.1"

    defaultConfig {
        applicationId "com.example.pf"
        minSdkVersion 15
        targetSdkVersion 23
        versionCode 1
        versionName "1.0"
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
	
	productFlavours {
		free {
			applicationId "com.example.pf.free"
		}
		paid {
			applicationId "com.example.pf.paid"
		}
		mock {
			applicationIdSuffix = ".mock"
		}
	}
	// Remove mockRelease 
	 android.variantFilter { variant ->
        if(variant.buildType.name.equals('release')
                && variant.getFlavors().get(0).name.equals('mock')) {
            variant.setIgnore(true);
        }
    }
}

dependencies {
    compile 'com.parse.bolts:bolts-tasks:1.3.0'
	  ...
	  ...
    proCompile 'com.android.support:design:23.1.1'
    freeCompile 'com.parse:parse-android:1.12.0'
}

define_product_flavours

productFlavours {
	free {

  	}
  	paid {

  	}
}

ignore_build

android.variantFilter { variant ->
       if(variant.buildType.name.equals('release')
               && variant.getFlavors().get(0).name.equals('mock')) {
           variant.setIgnore(true);
       }
   }

provide_dependencies

dependencies {
    compile 'com.parse.bolts:bolts-tasks:1.3.0'

    proCompile 'com.android.support:design:23.1.1'
    freeCompile 'com.parse:parse-android:1.12.0'
}