How can I use sqlite database file as my android app file format?

I have an android app project. I want to use the SQLite database file as my app file format, which I will use to export and import data to my app. http://ift.tt/1teGH1M does not say how can I do it. How can I use SQLite database file as my android app file format? I can create SQLite database file and export it to the user, BUT: how can I prevent anybody from changing my file? Because the exported database file can be read and edited as any SQLite database file. How can I prevent any one from making any SQLite database file and try to import it to my app? Notice that file extension make no difference in SQLite database files.