Is there an app for that?
 

Is there an app that will show your progress around a track (Lime Rock) and show where you are hitting/missing apexes, braking, etc.?

is this already available for the iPhone?

You would need super-accurate (differential) GPS for that to even be viable/possible I would think.

Harry's Lap Timer gives pretty good info. I think there is a free version for evaluation.

I dont know if Adyno or Alaprecorder have Iphone apps...

Alaprecorder


https://lh4.ggpht.com/47vppar90151Be...PQm-DMOWX=h230

I have them on my droid and they work pretty well

You also might be able to use Mapmyrun, but will probably be less granular and limited data

Unfortunately, the GPS sampling is good, but I don't think it's good for your proposed idea. It works well for things like harrys lap timer and other predictive lap timing apps, but it's not nearly as accurate as something like a traqmate.

For example, I'm in my front office right now, but my phone says I'm in my neigbours dining room about 15' away.

It may be better the the add on tomtom windshield mount, but by itself it's not acurate enough to differentiate a good line from a bad line.

PS - It's now showing that I'm in the front driveway working on my car - that's 10' in the other direction.

Check these guys out they might have something.
Quixey.com

trackmaster is on android and is pretty good on a phone's internal 1Hz GPS, but tons better on an external 5Hz gps!