I would like to have two applications, app X and app Y. X where a user can select from list of choices (perhaps a list) and Y then uses the selected choice of X upon start-up.
The reason I need this design is because the choice in X needs to persists even if the user clears data of Y.
Any suggestions on how I can do this on Android?
You can just write to a public file in the device internal memory (using XML, for example). More information.