How are they doing this with such accuracy?

[jpkoepse]

So I ride Motocross when I'm not programming and was thinking about making an app that can log lap times via Android's GPS(mark a finish line via GPS and everytime you pass this point it records the lap time). I've read that GPS isn't that accurate (between 3m to 10m). However I looked on Droid Market and there are apps out there with rave reviews that claim to be accurate within tenths of a second.

Do you think they are as accurate as people are claiming?

And what about the frequency of updates? I know you can set the requestLocationUpdates parameter to 0. So frequency isn't an issue with the timing correct? Just whether or not the location that is received and trips the "lap" is actually accurate to where you really are?

Jimmy

 

[jpkoepse]

bump?

 

[LASJayhawk]

if the gps is off by say 6M on lap 4 it will be off by 6M on lap 5.

Ie the gps may think the start finish line is 20 feet from where it really is, but will still think it is in the same place over short (an hour or so) periods of time.

 

[AngryHatter]

It's detuned by and for the military.