After restarting an activity of an Android app, the GUI state changes might lose, which is called as restart error.  Restart can be done at two levels: pressing home button and then launching the app again, pressing back button and then starting the activity again.

The Restart Error Detector Android project is to automatically test Android apps to find restart errors. It can navigate activities of an app by clicking buttons or menu items.

It can restart an activity at the two levels. It can change GUI element states, e.g., filling text boxes and checking checkbox.

It compare the states of GUI elements before and after restarting an activity. If the state changes are not preserved, a restart error is detected.