Harry's LapTimer Grand Prix App Reviews

While there are certainly more precise equipment and software out there available to the hardcore racers, its hard to deny Harrys work in his laptimer series. I owe both the Laptimer Pro and Laptimer trainer. For the cost of the apps, and the fact that I already had an iPhone 4 and iPad for other reasons, they are dollar for dollar, some of the best data acquisition and analyzing software a track junkie could invest in. For beginners: It allows for raw video recording followed by overlaying the data onto the edited video so that one may see the data of their lap in a fun manner. For the hobbyist: Simply record the session and sort through the laps to see how one handled each corner in terms of acceleration and cornering data. For a track junkie: Add additional external sensor for a data acquisition system that still costs hundreds to thousands less to anything else out there today. For instance, the internal GPS of the iPhone runs at about 1 Hz. Third party GPS sensors are available from $100 for a 5 Hz sensor, $150 for a 10 Hz sensor, and 20 Hz competitive sensor for around $400. The higher the hertz, the more accurate the time is, as well as the data acquisition. Again, best investment I have made towards my tracking experience.

It just works and provides tons of data for getting better on track

Was introduced to Harrys Lap Timer GP this weekend at COTA. Downloaded it to my phone at lunch, borrowed a friends OBD-II bluetooth scanner and iPhone suction cup mount and voila! I was in business. Incredibly seemless and powerful. Worked without a hiccup. Now I have memories and a learning tool to last a lifetime. Thanks, Harry! Well done!!

Fantastic app, ive been using it at track days and racing for several years. Get an external GPS device, mount it on your dash for the next track day, and you wont believe how usefull it is...

Excellent, Well done!

The information that this app delivers has been incredibly helpful to find a better line at the race track. Comparing the data collected from your personal fast lap to the fast lap of others shows you where and how to improve. Highly recommended. Thank you to those who are sharing their lap data.

Love this app! Works great for racing. If only I could figure out how after setting the direction to submit it and go back. I get stuck on that page and have no way out. If I could do that then I could certify some tracks.

Keeps crashing on iphone 6

This is a great product. Just by itself it is easily the best thing and easiest to use for improving laptimes. Great customer service as well when I was at the track and needed help. GTR Owners - I spoke with Harry, the GTR ecu is a bit wonky in how it works. So the OBD2 functions wont read proper values. He expects this to be fixed by version 19.1 which is expected no earlier than middle of this year. Just an FYI because I couldnt find anything on the forums about it.

Simple, concise, works.

Have been using this app since the old days on the Palm Pilot. Harrys dedication to continued improvement based on feedback from the user community and his own experience as a fellow enthusiast is unparalleled. Highly recommend the full "Grand Prix" version.

As a habitual DE driver I use Harrys Lap Timer and find it excellent. Is it pinpoint accurate (using the iPhones internal 1 Hz GPS)? No. But it is more than accurate enough to use for gauging progress, examining split times, recording video of your line, etc. Unless youre going to commit to serious data analysis of your lapping, Harrys is all you need. Great app!

Been using this app for 3 years so all of my complaints are of repeated use over this time. The crashing is just so frustrating, since I Autocross, tracks are not available and it seems the simple task of setting a start and a finish point results in an app crash every few times which requires re-walking to the start line and hoping it doesnt do it again (and yes it sometimes does and no if it crashes the poi do not get saved). Would help "A LOT" if you could set start and finish independently with the wizard.... GoPro video linking and downloads work properly about 5% of the time, it usually downloads the movie as an unlinked copy which is fine but the manual linking process is either out of sync or causes another app crash. Scrolling through graphs or opening graphs causes crashes constantly. The sync process for videos is really not intuitive at all, its easier to just try and repeat overlayd videos over and over until the PnP video is aligned. It needs to have a preview (maybe just 5 seconds of video), or split screen video, waiting 5minutes to render an entire file is silly. Deleting video should UNLINK it from a lap and not delete it off the device. Or have some undo, Ive accidentally deleted the wrong video a few times which is what really really really pisses me off and what broke the camels back. At this point Im done with the frustration and will use something else from now on, and yes there are other options out there.

Not worth purchasing (at the moment). The app is misleading if you have the latest iOS. The app will not support the multi-cam as stated in the description.