I tried the Race Chrono gps lap timing software on my phone and I can really recommend it. It gives sector times, speeds and also the lines your using on the track. The lines weren't really reliable as it showed that I was spending more time on the sand than on track but the timing was nice.
Link:
Check it out.
madagi
2008-07-23 07:58:00 UTC
Argon
2008-07-23 11:57:00 UTC
Post missing.
Nickeluring
2008-07-23 12:14:00 UTC
Post missing.