^Same company that makes this makes a really exceptional full blown app called "complete anatomy" for PC/Mac/iPads (newer)
iPhone (and maybe android)? can run essential anatomy. I use both, they are indispensable resources for learning or being in the field. I also REALLY like a book called "trail guide to the body". Its a typical anatomy text but coupled with really detailed breakdowns of palpating specific muscles, and they did some really cool videos with explanations on palpations coupled with pictures of the muscles overlaid on the human models.