Gradle file for copying release ready apk to desired directory.

publish.gradle

def getReleasePath() {
    //Define RELEASE_PATH anywhere(in properties file) and your apk + mapping file will be copied there.
    return hasProperty('RELEASE_PATH') ? RELEASE_PATH : "${project.rootDir}\\Release"
}

android.applicationVariants.all { variant ->

    //Mapping file for proguard path for each variant
    def mappingFile = variant.variantData.mappingFile

    //Right now only for release type (not debuggable and zipAlignEnabled)
    //Proguard must be enabled to get Mapping file, In future I will eliminate this requirement
    if (!variant.buildType.debuggable && variant.variantData.zipAlignEnabled && mappingFile != null) {

        //Get Current Date and split it into yyyy,MM,dd to create directory structure reflecting to it.
        Date date = new Date()
        def y = date.format("yyyy")
        def m = date.format("MM")
        def d = date.format("dd")

        //RELEASE_PATH property or project's dir\release.
        def releasePath = getReleasePath()

        //Get Project Name to make directory
        def projectName = project.parent.name
        //File path will be generated Like : ReleasePath/ProjectName/Y/M/D
        //e.g.: D:/Codes/Release/ShareChannels/2015/07/02
        def filePath = "$releasePath/$projectName/$y/$m/$d"

        //Directory name by version, where apk and mapping will be stored
        def dirName = "$variant.versionName - ($variant.versionCode)"
        File release = new File("$filePath/$dirName")
        //Mapping Directory: Will be part of original Directory
        File mapping = new File("$filePath/$dirName/Mapping")

        //APK File To copy
        def apk = variant.outputs.outputFile

        //Main Container task.
        def publishTask = project.tasks.create("publish${variant.name}")

        //Task for copying mapping file
        def copyMapping = project.tasks.create("Copy${variant.name}Mapping", Copy) {
            from mappingFile
            into mapping
        }

        //Task for copying apk file
        def copyApk = project.tasks.create("copy${variant.name}Apk", Copy) {
            from apk
            into release
        }

        //Task for Creating directory
        def prepare = project.tasks.create("Prepare${variant.name}Directories") {
            mapping.mkdirs()
            release.mkdirs()
        }

        //Now dependency tree: First APK should be created, which will give us mapping and apk files to copy.
        prepare.dependsOn variant.assemble
        //Then create directories.
        copyMapping.dependsOn prepare
        //first copy mapping file, then apk file
        copyApk.dependsOn copyMapping
        //Now just run Publish Task and your apks will be copied easily.
        publishTask.dependsOn copyApk
    }
}

//TODO:

1. Put Publish task out of applicationVariants block. It will stop creating all the folders all the time.
2. Add Grouping and Description of each task
3. Add Google Play publishing code.