I ordered two of these. I really liked the Android phone interface, however two things I didn't like were: 1) the "fob" that attaches to key must be charged via USB cord, there is no replaceable battery. 2) Five minutes after a "full" charge, my Droid RAZR told me the battery needed charging. More than once. I never opend the second one, just returned both.
Too bad, I really wanted it to work.
Update Feb 11th. I ordered another as I have several people that want one if the charge will hold on new device. Will update again after a few days.
After two more days: I still like what it does, the dongle seems to have a seven to eight HOUR charge cycle, hardly as advertised as seven DAYS.
After a week. Same results. About seven hours continuous use. If they made the fob with a replaceable battery, THEN it would be worthwhile.