Multiple APK support is a feature on Google Play that allows you to publish different APKs for your application that are each targeted to different device configurations. Each APK is a complete and independent version of your application, but they share…| Android Developers
Lets you express an application's compatibility with one or more versions of the Android platform, by means of an API level integer. The API level expressed by an application is compared to the API level of a given Android system, which can vary…| Android Developers