Data log with your iphone
 

http://www.autoblog.com/2008/07/29/d...ormance-meter/

Ok I just put it on the wifes phone and took it out for a test. My car has dynoed just shy of 200whp (199).

0-10-1.51
0-20-2.46
0-30-3.36
0-40-4.46
0-50-5.68
0-60-6.94
0-70-8.60
0-80-10.33
0-90-13.13
60' 3.21@27.5mph
330' 7.14@60.00mph
1/8 10.29@79.5
1000' 12.96@88.7
1/4 15.27@98
Max Acceleration 1.29g
Peak Horsepower 188


I'd say its pretty accurate. I spun all of first and half of second. The car is a 2004 MSM with 205/50/15's Azenis.