Harry's Lap Timer with OBD2 WiFi Adapter

I've just downloaded Harry's Lap Timer for my first trackday tomorrow :smile:

Anyone know how well it functions with the standard internal sensors? (I have an iPhone 5).

Also, I really want to overlay the selected gear and the revs in the future, which I need an OBD2 adapter to do. Can anyone recommend one? Looads of cheap ones out there but very mixed reviews! Was considering this one:

Haha to be fair the reason I downloaded it in the first place was because I'd been searching through old threads and saw him raving on about it :smile:
Nice footage! Yeah the speed messes up around the first corner pretty bad! Apparently an external GPS sensor will fix that but again the ones Harry recommends on his website are super pricy. Haven't looked to see if there are any cheap and cheerful ones available.

Yeah I'd love to overlay some OBD2 data, I'd just rather pay £10 than £100 :smile:
Post up what you find and end up buying along with your results. I'd love to do the same but again cheapie cheap.


lol i missed this, i'm a beta tester so yes i know the app very well.


I was out the country from the 17th for 3 weeks which is why i missed it.

for the OBD via bluetooth, you either have to go point bt1 which is around £100,
OBDLink Scan Tool around £75 or PLX Kiwi 2 wifi again at around £100 but if you go the wifi route heat may be an issue.

I ALWAYS have aircon gently blowing on the screen to help combat it even tho i don't use wifi.

the only CHEAP way is to jailbreak your iPhone and then buy a £3-£5 app (roqyBT4) and a free add on roqyOBD4 that allows you to use a £10-£20 bluetooth obd reader. i use ONE OF THESE.

you then add custom settings to HLT, plug the reader in, start the car, open the app roqyBT4 connect to the obd and then open HLT.

That sounds complicated but isn't and i can do a video for you but there are some drawbacks. Obviously you need a jailbreak which isn't always the current iOS although it is current for 7.0.4 so you can't just update your phone to the new iOS. Secondly it isn't supported by HLT.

RoqyBT4 isn't compatible with iOS 7 as the jailbreak was only released on christmas eve but the developer is working on the update and has said to be patient as he now has to support arm64 for the iPhone 5s as well as the A5 and 6 chips in other iOS devices. I have his beta release and that is stable but needs a further tweak and the developer is still testing the OBD part before releasing it for beta.

Once he does i will test it and produce a video so you can see how to set it up. :thumbup1:
A bit off topic, but if you get the Kiwi Wifi adaptor from Wombles post, are there any good error code reader apps for iPhone?


A bit off topic, but if you get the Kiwi Wifi adaptor from Wombles post, are there any good error code reader apps for iPhone?
There is dash command or if you have a bluetooth laptop/pc then i can give you ScanXL Professional patching tool :thumbup1:


Ok for those with it and jailbreak to pass OBD data, then i can now report success on iOS 7.0.4 with roqyBT7 & roqyOBD7

This will shorty be available in cydia as i have had the beta versions and now the soon to be published alpha versions.



I will try and do a walk through video on monday to show you what to do


Here is the video on what to do. :giggle:

Don't want to jailbreak my phone so just bought this from Womble's recommendation (link)

Tested it really quickly just now and it seems to connect okay and HLT & Rev Lite recognise it as an OBDII device :smile: I can't see any readings yet although I think (hope) the engine needs to be on for that.

Will go for a drive after gym & F1 and hopefully return with good news and some kind of video

Edit: 200th post :wink:
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Cheers for letting us know, all I'll say is wifi will hammer the battery so ensure you have a power supply and it will also increase heat in your iDevice so keep it cool or it will shut down.
A bit off topic, but if you get the Kiwi Wifi adaptor from Wombles post, are there any good error code reader apps for iPhone?

iOBD2 is exceptionally good. You can do all sorts with this one. The app is free (i think) but I had to pay £14.99 to add Wi-Fi and Bluetooth 4.0 support so I could use the ELM327 wifi OBD2 module from ebay.
Got tied up over the weekend and didn't get a chance to upload the vid.. will try and do it tonight.

To summarise though.. the device seems to work but it appears very slow at updating information; there is a pretty significant 1-2 second lag which is annoying. Though this could possibly be solved by shifting the overlaid data by 1-2 seconds, I'm not sure.

The worst part though is that the displayed gear is always one out when in 3rd and above! So 1st is fine, 2nd is fine, 3rd is shown as 2nd, 4th shown as 3rd etc. [MENTION=3821]Womble[/MENTION] have you had anything like this at all? Could you upload a HLT vid recorded while using the hardware you posted?

I have only tried it with HLT as Rev lite doesn't actually let you view any OBDII stuff! So I'll see if I can find a free app to check the displayed gear on.


Have you set the transmission details in the vehicle list? Along with all the other data?
Yeah just checked the details in the vehicle list and they all seem correct.. though displacement was at 3500cc for some reason so I've put it to 2000cc but that shouldn't make any difference.

Number of gears are at 6 but not sure if all the ratios are correct (they're probably not!)

Edit: currently uploading to the YouTube.. only 135 minutes left :coffee:
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