Sometimes I get strange values for speed and course in didUpdateToLocation. This probably started when I changed the desiredAccuracy setting from kCLLocationAccuracyBest to kCLLocationAccuracyBestForNavigation. The course could drift up to 90 degrees. Another problem is that the speed sometimes is set to 0 if the device is perfectly still(even if the boat/car is moving). I don't know if the problems are related or not.
I can confirm this behavior on several devices both ipad2 and ipad3.
Has anyone experienced anything similar?
/Martin