Robotium allows writing and running test cases for the pre-installed applications in Android. To do this, you need to perform the re-sign operation on the target application with the debug key that you are using for the test project. This requires access to the
/system/app folder on the device. To access this folder, you must have a rooted device.
Please note that some of the preinstalled applications for which the re-sign operation is performed don't work properly. These applications don't even show up when re-signed with the new debug key.
To re-sign an APK file, you can follow the listed steps: