Using four different timing methods, I compare the accuracy of them all
#1 GoPro @720P 120FPS, imported @ 60FPS, which was 0.017s per frame
#2 TBS RaceTracker
#3 Airbirds EasyRaceLapTimer PocketEdition
#4 DVR @25FPS, which was 0.040s per frame
The GoPro has an error rate of up to 0.017 as that is how long a frame is.
Here is the average variance of the timers for the laps:
TBS = 0.0126 - within the error range of the GoPro, so could be more accurate
ERLT = 0.223
DVR = 0.141
GoPro Laps:
16.75
16.116
16.333
16.583
16.883
TBS RaceTracker Laps:
16.769
16.145
16.345
16.59
16.879
EasyRaceLapTimer Laps:
16.48
15.89
16.16
16.34
16.68
DVR Laps:
16.6
15.96
16.24
16.44
16.72