What is Android SDK version?
Android SDK Version 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 will be compared to the API Level of a given Android system, which may vary among different Android devices. Despite its name, this element is used to specify the API Level, not the version number of the SDK (software development kit) or Android platform.
The API Level is always a single integer. You cannot derive the API Level from its associated Android version number. To define the version information for your app, set values for the version settings in the Gradle build files. These values are then merged into your app's manifest file during the build process.