Summary: I bought this receiver to attach to an HP Hx4700 pda (another e-bay purchase)in an effort to make a small, portable and inexpensive aviation gps. Since it's listed as an automotive gps, I did not know if it would be compatible with aviation gps programming, although the same signals are received. Installing the gps program was easy. Setup of the Holux receiver was simple and intuitive. To my surprise, the resulting gps unit works even better than I had hoped!