I've been playing around with car insurance apps that track your driving via phone. I'm running several, but only one will actually give me a map and how me where I've been and indicate where it thought I drove poorly. It doesn't give exact speeds, but it will gig me if it thinks I went over 80mph. The other day, it nailed me for it twice- once at the start of a curve on the freeway and a second time at the end of the curve; the points were roughly 2.5 miles apart. I thought it was BS because I was watching my speed... normal watching- not crazy staring at it. Anyway, I did the same drive again, but this time, the driver I was following had cruise control set and stayed at 69 the whole time, so I decided to stay behind him on purpose, all while closely monitoring my speed. I did not go over 70. I am certain. However, the app clocked me at 80+ again on the exact same curve.
This won't impact me because I'm not going to buy car insurance from that company. However, I believe their app is faulty and will impact other drivers. That said, I cannot find any info on what would cause an issue like that. There are no tunnels. However, the zone is right up against a major airport and there are mountains about 3-4 miles to the northeast and roughly the same distance to the south. Could either of those things cause the gps-based speed to be off by 10+mph? Could something else cause it? For what it's worth, none of the other apps have caught this problem- they all say I'm a perfect driver, though I can't even tell if they monitor my speed. I'm assuming they do and that it's part of my overall score.
Randy D 