Why don't you want to use the shared preferences? This would be by far the easiest. Of course you can think of more complicated ways that don't use shared preferences, but you have to store it somewhere. Some messier ways:
- use a SQLite database
- use your own file format
- use a unique device id (careful, Android ID is not really unique) and store it on a remote server
- store it in a really crazy way, such as a special text message, or a contact, or ...
- find some way to change your application code (might be possible on a rooted phone?)
To summarize: SharedPreferences is made for this type of thing. It works. Use it. No really.
