ignore only beam files
What is the reason for this? The original .gitignore ignored the whole ebin/ directory.
But why you store .app file in that directory?
I don't. I believe it was (accidentally) committed to the repos once, but Joe Norton removed it in a commit Feb 24 2011.
I've added ebin/.gitignore now, since users of -include_lib("gproc/include/gproc.hrl") may run into trouble without it.