High accuracies (small values) are certainly preferred. But I'd never trust the values calculated, they are heavily chip dependent and can be tweaked just like your car's speedo I'd suggest to not compare two chips against each other but instead use accuracy as a relative value showing if one receiver is in good condition currently or not.
On the speed I'd suggest to contact Romain from roqyBT. LapTimer uses the same interface for both the internal GPS and one feeded in by roqyBT. As the speed freezes for the external GPS and not for the internal, this means the input from roqyBT freezes. I'm sure Romain can help here.
Every "->" makes a conversion and may be the place speed gets lost. The "roqyBT -> iOS Location Service" seems to be the issue. To enjoy a directly integrated GPS Sensor you may try your QStarz with LapTimer Rookie available for Android
I have an android handset I can use but then as we both know I'll miss out on the video capability, which was worth the purchase price alone to not have to run 2 devices, export data, and do overlays later.
If all else fails, for $100 I can gram the Emprum, though I'll have forfeited my Roqy costs and will have to sell the Qstarz, but at least it will work.
At least I'm testing it all before a track day and not getting caught out with no data at the track.
iPhone4s 16GB, Jailbreak on iOS 6x, RoqyBT4, QStarz BT1000 (in 5hz mode)
Using PetrolHead
Had a go at recording video on the drive to work and noted that at no point during the trip was speed recorded.
It traced the "track" properly as I'd defined a new one (though I just realised I'd defined the "start" as "start/finish" accidentally). GPS signal was solid, 4-4.2hz the whole way.
I started and stopped the recording manually and after examining data there's no speed recorded.
Was it maybe that manual recording was not enabled in the settings?
Also, The main reason I wanted this app and paid for it was the ability to do it all on one device (video, timing, and overlay - as I used to use a seperate camera and phone with RaceChrono then overlay later).
An 18min trip to work resulted in a 2.7GB file, but then wouldn't allow me to overlay the data, stating that I needed another 400mb or so of space, despite having around 6.5GB free (and that's AFTER the video was recorded not before). I'm happy to clear the phone after each track session (usually around 20mins), but I'll be left high and dry if I've paid for an app and I can't export a single sessions worth of video.
I heard that a New Jersey guy seriously affected local aviation system by a small jamming gps device. So, gps is not always solid.
Is there a way to control background data app refreshing on iOS6.x like there is on iOS7?
After more testing, and no response from Romain (or is it Roman), It looks like once the app is switched away from (switching away from Roqy to access LT) that's when transmission of data stops.
I'd suggest to not compare two chips against each other but instead use accuracy as a relative value showing if one receiver is in good condition currently or not.
