What are AT&T subscribers buying, downloading, and using on their handsets? The carrier has released its top-selling apps for the first quarter, and we've got to admit, the results aren't very surprising at all. Not including games, MobiTV takes the top spot -- likely in part because AT&T pushes it so hard -- and the ubiquitous thriller Tetris is the number one game. Makes sense, but do you agree? What have you been downloading lately?