I found this app recently while searching for an overlay solution for AutoX and other racing videos. After reading several reviews and watching many YouTube video's of other's using this app when recording their track runs, I bought it.
Here's a pic of YouTube that shows it in action:
Currently, there's three purchase options:
LapTimer Product Family
LapTimer Rookie Edition (no video or overlay) - $8.99
LapTimer Petrol Head Edition (video and overlay) - $19.99
LapTimer Grand Prix Edition (video, overlay and multi-cam support) - $27.99
All three are currently available on iPhone. The Rookie Edition was recently ported to Android and the other editions will be arriving throughout next year.
This is not a 0-60 app or a dyno app. As the name implies, it's an advanced lap timing and track recording app. It turns your iPhone into a $800+ racing telemetry powerhouse. You can even enhance the app with external devices like a more powerful GPS and OBD wireless/bluetooth connectors.
No, I am not a salesperson. I am just overly excited that I found this app. $27.99 may sound expensive for an app, but considering what it offers and the little testing I have done so far, $27.99 is a steal compared to a full fledged stand-alone device.
I paid the $27.99 and bought the "Grand Prix" edition. I will be using my iPhone as the front camera and GPS device. The Grand Prix edition can also trigger my GoPro and an additional iPhone for multiple camera angles.
I don't have time to do a full review just yet but will be testing this app out at tomorrows AutoX event. Shortly there after, I will post a review of this app. In the meantime, you can find more info out by either googling "Harry's Lap Timer" or going to his website: http://www.gps-laptimer.de/Home.html