Android Project: How best to organize the files

I'm building my first android app, and it's gotten a little messy already. I'm using List/detail patterns because they're what fit the circumstances, but because I'm developing for both mobile and tablet it's getting a bit out of hand. For every screen (List/detail being one screen), four files are created. ListActivity, ListFragment, DetailActivity, DetailFragment. Having four screens so far, and literally just starting the project, I have 12 files, plus three helper files for one database table.I'm building my first android app, and it's got