anyone have any experience or thoughts regarding the accuracy of the iphone for gps?

Analysing GPS data

Have a iPhone 3GS and a Garmin Forerunner 405. The Garmin is constantly accurate. I got sick of the amount of rides I would have just using the iPhone where I seemed to have rode across a body of water or taken a 10 mile detour and back in a few seconds.

..but then this is to be expected as the Garmin is a dedicated GPS unit.

The iPhone’s GPS chip is a little hobbled by a small antenna. It also *chews* battery when the GPS is running even with the screen off. My personal preference would be for a separate, dedicated GPS device. I love the iPhone, but in this respect the GPS is simply not accurate enough for consistent periods of time. It’ll do just fine for “show me stuff near here” or “give me a route from here to somewhere else”, but tracking your progress in real time can (and does) trip it up.

I just wish there was an easy way to hook up an external GPS antenna to it without having to jailbreak it. There are bluetooth GPS antennas out there that work with it that make it extremely accurate and responsive, but you need an app that can interpret that data (that then makes it available to normal apps as if it’s using the internal GPS), that is not available via the App Store – you have to JB.

I have a Garmin 305 and an iPhone they Garmin will just take the edge but the iPhone works pretty well. Eats battery life on the iphone but you still get a good few hours out of it.

Slightly off topic but I have been using Google My Tracks on Android (Google Nexus S). Not so severe on battery (get a good day’s ride in) and obviously integration with Google Maps is excellent as well as ability to export to GPX, KML etc etc. Nice stats output including moving time and moving average speed as well as total time / ave speed, ascent / descent etc and seems pretty accurate.

Iphone battery will last a max of 4 hours using gps, i prefer my garmin.

been using everytrail on the iphone 4. download a gpx file then upload it to everytrail and load the map over wifi at home. this is handy if there is no 3g signal and you are trying to find out if you have gone off route.

you can edit the routes online

i just use it as a back-up to following a route and to record the route at the same time. i was left with more than 50%battery power after a 5hour ride so on the 4 it’s not a problem.

it’s not going to replace a proper gps but it means i don’t get lost.

My Edge is a lot more accurate than my iPhone4, especially when under cover of trees. It’s not too bad in a straight line, but when you start putting in tight turns/switchbacks the iPhone tends to straight line them, on the Garmin you can clearly see them.

As others have said – iPhone is fine for a short amount of time but kills the battery – If you use it don’t rely on it as a phone.

Garmins are far better for longer rides

I use my iphone for tracking rides but not really for navigating (unless it’s just a reroute mid ride) – I use a ‘proper’ Garmin gps for that.

That said, the main reason is waterproofing/crash resistance – I don’t want to trash my phone whereas my gps is designed to sit on the bike. I’ve actually found the accuracy of my iphone pretty good – it’s not usually significantly different to my garmin if I compare after a ride.

FWIW, I’m using the EveryTrail Pro app which run in the background (made a big difference when background running was allowed in OS3.0(?)) will allow about 5-6hrs run from a fully charged battery on my 3GS.

Iphone 4 GPS battery life is very good

If I’m doing a long ride I will make sure Wifi and network data are switched off though

having said that I only use it to track miles ridden etc via cyclemater – I don;t use it for navigation. The more you switch the screen on during a ride to check your route, the worse the battery life will be. And I wouldn’t be mounting my phone on my bike

Very interesting regarding the Android app. has anyone else got experience of this? Hadn’t even thought about that. Does anyone have any experience of which different GPS add on units can be used?

For those worried about battery drain on the iphone:

http://www.amazon.co.uk/Micropix-1900mAH-External-Battery-Classic/dp/B0035KH95Q

As others have said – iPhone is fine for a short amount of time but kills the battery – If you use it don’t rely on it as a phone.

there is a big difference between the 3-3GS and 4 battery life and even between different apps.
runkeeper is a good app but was a killer on the 3g battery, everytrail lasted a bit longer. on the 4 they are good for 6-7 hr rides, probably longer but i haven’t ridden for longer than that.

The iPhone 4 is much better and all you really need accuracy wise, unless you are a bit anal about wanting to where you are/where you have been down to the last meter.

I use Viewranger to navigate and track and its brilliant. OS mapping for £ or open cycle map for free and no data needed out on a ride.

I can track for 6 hours and still have 50% battery life if I turn of 3G and WiFi (which are usless when riding anyway).

The track accuracy depends a lot on which app you are using.

The only downside is the ruggedness and fragility of the thing as you really don’t want to get it wet or land on it. Strapping to the bars is a no-no.

I have this case for mine – fully waterproof though a bit bulky

http://www.amazon.co.uk/dp/B003SAIBGE/ref=asc_df_B003SAIBGE2381699/?tag=googlecouk06-21&creative=22134&creativeASIN=B003SAIBGE&linkCode=asn

Does anyone know of alternate software to log Edge 205 data, rather than using the Garmin PC app. Something similar to Sports Tracker online maybe?

I find a sandwich/freezer bag works brilliantly as a waterproof case, and you can still use the touch screen with it on.

My favourite GPS App on the iPhone is Memory Map, download the map you want before the ride, then you have an OS quality map for when you get lost!

I find a sandwich/freezer bag works brilliantly as a waterproof case

I thought that too until a very wet weekend at Afan proved me wrong… The idry allows you to use the screen without opening it up too.

iPhone logged route (using EveryTrail) from last night – lots of it under tree cover – it tracks the trails pretty well I reckon.

http://www.bikely.com/maps/bike-path/500151

I’ve looked into multiple waterproof cases myself. I’ve found many to be bulky and expensive. I already have a protective case on my phone and I’m going biking not swimming. I came across this iLoc case I might give a shot since it’s only a buck for two (ilocstore.com). Looks perfect as I can use one per outing and it fits perfectly in my side pocket on my backpack.