Harry's GPS Laptimer - Anyone Used?

[RobOpel]

Hey guys,
It looks like this laptimer question comes up every year or so, but I haven't seen if anyone is using the Harry's Laptimer app for IOS or Android.

Right now, I'm using my garmin cycle computer as a laptimer. It seems to have good positional accuracy, but the sampling rate is 1/sec, so it can't have super great timing accuracy.

Anyway, it looks like this Harry's app has good functionality, and can be expanded with a bluetooth OBD dongle to get TPS, gear selection, rpm, ect.

So, has anyone used it or can anyone comment on its accuracy with the phone gps or one of the external gps?

Thanks!

Rob

 

[i-Zapp]

I've used Harry's for a few years now. Perfect thing for an older iphone 4 you don't care about anymore, and with a Bluetooth GPS unit (about 150 bucks for a Dual XGPS150) the total investment is less than 200 dollars. I've never compared the relative accuracy to my XT Racing timer (infrared), but figured that if the times were accurate within a few tenths I'd be happy. The nice part about HLT is the richness of the data you get - mph, g-forces, etc that make evaluation of your progress easier and if nothing else more fun. And of course, if there's no beacon for your XT you're SOL unless you've got your handy HLT. Btw, if you don't opt for the BT GPS, I think the iphone will update at about 1 to maybe 4 Hz. Not great, but you can still get lap times.

The lap below is from MidOhio. The map view displays G forces. You'll also notice that on the charts if you zoom into the graph, it will highlight where on the track that data was generated.

 

[i-Zapp]

I should note that the data above was generated with the INTERNAL gps unit of the phone at 1 hz (not a BT add on). the software is pretty sophisticated in that it can interpolate between the 1 hz samples to generate a more accurate lap time than the 1 second sampling interval would suggest.

 

[Kruizen]

I've got an external gps (dual gps) receives at 5hz that i used with Harry's. Connects to the phone via Bluetooth, charge lasts all day.

I don't use it anymore, make me an offer of your interested.

 

[RobOpel]

Ok, that looks about like what I had in mind. It sounds like you can also export to csv for any higher level analysis, so that is definitely a plus too.

Kruizen, I have to get with the times and get a better phone first, but I'll let you know when I'm in the market.