Originally Posted by kurichan
If you were in downtown Chicago among high rises, the device might not have been able to locate satellites. Common, often forgotten problem with GPS.
This is true, however, that shouldn't prompt him to upgrade to the premium version of Sprint Navigator. In Sprint Navigator, when you're out of GPS coverage, you get an audible alert saying "No GPS coverage in this area" and then when you return to GPS coverage, you get an audible alert saying "You now have GPS coverage".