The legal research service Fastcase recently released an iPhone app that lets you research cases and statutes on your iPhone for free. The app provides the largest free law library available on the iPhone. (LexisNexis offers a free iPhone app, but it is only for the Get Cases and Shepardize functions.) It includes cases from all 50 states and the federal courts, as well as the U.S. Code and most state codes.
Not only is the app free, but all research on the iPhone is free as well. A subscription to Fastcase is not needed. First-time users, however, must register for a free account.