Compatible with most Pocket PCs with a CompactFlash slot, the Pharos Pocket GPS Navigator with CompactFlash includes Pharos' iGPS-360 convertible receiver with a CompactFlash adaptor. Use it directly connected to the CompactFlash Adaptor, or for added flexibility use the CF extension cable for placement and reception. There is no need for an external antenna! With Ostia, Pharos' award-winning navigation software installed on your Pocket PC, you can drive or walk through any city in the US, and locate your current position or quickly find a destination or point of interest. Routes can be calculated and viewed. The automated voice prompts will instruct you when and where to turn. If by chance you go "off-route", the automated voice will give an off-route warning and the system will automatically reroute you to your destination from your current position.