Nike+ iPhone GPS 6% different?

Finished Get Running? Tell us how you did, and chat with other Get Running graduates about what to do next!
Post Reply
Posts: 20
Joined: Mon Sep 16, 2013 10:34 am
Location: Boynton Beach, Florida, USA

Nike+ iPhone GPS 6% different?

Post by alanmcd »

What kind of accuracy are you seeing with your GPS running devices?

I ran a 5K with both iSmoothRun and Nike+ running apps on an iPhone 5 (simultaneous, not one then the other). The Nike+ decided that I had reached 5k about 0.3k before the iSmoothRun decided I had reached 5k.

Alan (Still doing a 5k about every five days).
Posts: 341
Joined: Mon Oct 24, 2011 3:22 pm
Location: Lexington Park, Maryland

Re: Nike+ iPhone GPS 6% different?

Post by starknut »

Many people have reported higher accuracy with Nike+ since it updated for iOS7. My problem was the opposite: my distances became wildly inaccurate and I had to recalibrate.
User avatar
Posts: 136
Joined: Sat Jan 09, 2010 1:54 pm

Re: Nike+ iPhone GPS 6% different?

Post by matt »

I don't think two GPS apps will ever read exactly the same. There's a few different factors involved: the sampling rate, the "smoothing" of the results, error detection and correction (sometimes a GPS's accuracy will drop and you'll suddenly "move" two miles from where you were for a few seconds, then come back -- the GPS app has to decide how it should ignore/cope with that kind of thing.)

The GPSes in phones aren't generally that sensitive, either, and it doesn't help that the phone's often in a pocket. Plus if you run through a forest, tall buildings, etc. it can have quite a significant effect on the results.

This is one of the reasons I've always been against putting GPS into Get Running itself: I think a beginner has enough to cope with without making the app possibly less reliable and more confusing.

A lot of that is based on my own experiences running with other apps that did have GPS built in, where sometimes it would work, sometimes it wouldn't, sometimes the results would differ wildly from reality, and sometimes it would even seem to crash the app. It also drains the battery on your phone quite fast -- my phone only just made it to the end of my first half marathon with the GPS running.

In the end I bought a Garmin Forerunner GPS watch, which has a great GPS unit, goes on your wrist where it can always "see" the sky, and has a rechargeable battery that lasts for a lot longer without leaving you with a dead phone if it dies, too. They can throw your results up automatically to Garmin's own site -- some other sites support import of Garmin stuff (RunKeeper supports my old watch, not sure about the newer ones: if you're in the market for a GPS watch, check that it'll work with your favourite log-keeping site before you buy, if that's important to you!)

So, if you want really good GPS results, I'd recommend a dedicated runner's GPS like the Garmin. On the other hand, you've got to spend more money, have an extra gadget around the place, and remember to charge another thing before you go you out...

Matt. Splendid Things web guy and Android developer. Started running with Get Running in 2009. Three 10Ks and six half-marathons done since then :)
Post Reply