This sample demonstrates how to design an application that is compatible across different Android versions. Applications should degrade gracefully on older platform versions, dropping features or providing when the platform support needed by features or functionality isn't available.

In this case, the CrossCompatibility application shows how to use APIs that are not available in all Android versions and still create a single `.apk` that runs on all Android versions.

- The main application's AndroidManifest.xml file declares that it is backwards compatible with API level 3 devices with attribute `minSdkVersion` in the `uses-sdk` tag.
- VersionedGestureDetector.java is a version independent abstract class which factors out multitouch APIs that differ between platform versions.

For more information on how to make your applications cross-compatible, please check out the original blogpost here.