San Francisco - Google (NASD: GOOG) on Wednesday announced the beta launch of a new service that will enhance its mobile mapping system by calculating the position of cell phone users, based on information broadcast from cell towers. The My Location feature, basically a workaround for non-GPS-enabled mobile devices, is accurate to within about 1,000 meters, and will initially work with all color BlackBerry devices, all Symbian Series 60 3rd Edition devices, most Windows Mobile devices, newer Sony Ericsson devices, and some Motorola devices. Notably absent is Apple's iPhone, which uses Google Maps and does not have GPS.