All Android phones that I am aware of have stand alone GPS units built in. Stand alone means that they don't have to have data to work. However, they also have a function called aGPS, which uses data to download a rough set of satellite positions based on cell tower location to help the unit lock on to its position much quicker. The amount of data downloaded by the aGPS function is extremely small, but it speeds up satellite acquisition (time to fix) drastically. After the lock is made, data is no longer needed.
Hope this helps,