Garmin Ltd and Navigon AG announced today that the two companies have signed an agreement for Garmin to acquire privately-held Navigon AG. Known in the iOS community for its very popular MobileNavigator series of turn-by-turn GPS apps, Navigon also manufactures a number of portable navigation devices as well as developing software for PNDs and other smartphone platforms. In announcing the acquisition, Garmin’s president and COO Cliff Pemble…