If your handset doesn't get you out and about, tramping through mud, climbing around and hunting for hidden treasure, then something needs an upgrade. The iPhone, Blackberry's Storm and Bold lines, and many Symbian and Android handsets, now sport GPS, which makes your smartphone the ticket to join a global movement of outdoor games. These are outbound challenges that pit teams and solo players against themselves and each other in the search for hidden treasure, undiscovered landmarks, and hidden spots all over the world. This article delves into several of the best smartphone-friendly real-world games, each of which is a bridge between the online and offline worlds."