mudguard wrote:How much more accurate is a dedicated device like a Garmin of some kind over a phone for gps?

My experience is that different phone vary MASSIVELY with their GPS accuracy, I don't know if its a make, a model, an age or how many times you've dropped it thing. But as a general rule the dedicated units are better than a phone.

More importantly they don't leave you stranded in the middle of nowhere unable to call international rescue if their battery goes flat.

Whats the best value for money stand alone GPS that has HR at the moment?

I've been looking at this: http://www.dicksmith.co.nz/health-fitne ... snz-se5098

Seems really good for the moolah if you're not worried about cadence.

I have a good comparison of Garmin and iPhone on a BIG ride, the iPhone map trace looks awful due to GPS drift / spidering, but the totals are surprisingly close, Garmin mounted on bars, iPhone in back pocket.
Might need to be logged in to Strava to see the maps properly:

Garmin Edge 500 Everesting Distance: 190.2km, Moving Time: 14:20:55, Elevation: 9,258m
iPhone 4 Everesting Distance: 191.0km, Moving Time: 10:14:50, Elevation: 9,506m

Like Rik said there is shocking variation between different devices, I've seen the same ride at 200m and 1300m elevation trawling through Strava files.

dave_sharpe wrote:

mudguard wrote:How much more accurate is a dedicated device like a Garmin of some kind over a phone for gps?

For GPS, not much in my experience - elevation is where I've noticed the largest difference. For example, a cruise around The Bays in Wellington has about 220m climbing (inc the haul up to Brooklyn), but the Strava android app regularly charts up near 1,000m for the same route...

I've seen something similar (although not 700+ extra meters ) of climbing added, the elevation around all the right hand corners up a section of summit road strava thinks there is a 10-15 odd meter drop part way around then climb back up again. None of them do that but I guess its the gps signal having a sook from the proximity to the cliff (which is on the left hand side)

Scotty wrote:I've been looking at this: http://www.dicksmith.co.nz/health-fitne ... snz-se5098

Seems really good for the moolah if you're not worried about cadence.

hmmm tempting, and the hr strap is on special too.

phunk wrote:

Scotty wrote:I've been looking at this: http://www.dicksmith.co.nz/health-fitne ... snz-se5098

Seems really good for the moolah if you're not worried about cadence.

hmmm tempting, and the hr strap is on special too.

Tried to buy it but DS wont let me, what a pooze website.

Rik wrote:

mudguard wrote:How much more accurate is a dedicated device like a Garmin of some kind over a phone for gps?

My experience is that different phone vary MASSIVELY with their GPS accuracy, I don't know if its a make, a model, an age or how many times you've dropped it thing. But as a general rule the dedicated units are better than a phone.

More importantly they don't leave you stranded in the middle of nowhere unable to call international rescue if their battery goes flat.

Not used a dedicated GPS, but I enjoy comparing the strava logs of rides with mates.
Same ride, same time, different phones and quite different distances / altitudes covered.

Personal fave is Deliverance - nice deep valley, thick bush, clouds... Strava packs a proper sad and squiggles all over the show.

mudguard wrote:How much more accurate is a dedicated device like a Garmin of some kind over a phone for gps?

depends - I did some tests of a GPS watch vs a full sized handheld GPS a few years back (nike sportwatch+ vs garmin oregon 600) and the oregon had better accuracy, especially in 'difficult' areas (deep valleys which means you can't see many satellites). However I've since gone to a garmin vivoactive for running, and it's pretty close to the handheld in terms of positional accuracy (mainly down to supporting gps+glonas same as the handheld, and undoubtably a bit of progress on the hardware side).

Only issue with the va is it's logging intervals - would be nice if you could just set it to 'every n secs' but instead it tries to be overly clever and base log frequency on your speed, which is fine except when you're running lumpy terrain (so it slows down logging on the ups - which is fine - but takes a bit to respond when you accelerate on the downs, so plots look kind of chunky the those points)

adikt wrote:I use runkeeper & strava,

It's interesting to see how differently they measure the same ride

it gets worse - feed the same gps data into mapmyrun/mapmyride, strava and garmin connect - then compare the 'total ascent' calculated between the three. MMR obviously applies massive smoothing, but even strava and GC can't agree (and all three are leveraging the nasa dem data)

Scotty wrote:I've been looking at this: http://www.dicksmith.co.nz/health-fitne ... snz-se5098

Seems really good for the moolah if you're not worried about cadence.

I have a spare cadence sensor that I could be convinced to part with if you wanted it.

Argh, what drives me nuts is how Strava (or likely my phone) sets off segments earlier. Today is a really good example. Rode in Rotorua, rode up to Billy T. Naturally had a rest about 50m above the entrance (get a little momentum). Work phone rang, so talked for 10 minutes. Checked fork air pressure blah blah, then into it.
20:39
Average 6kmh. Which was slower than my climb up!
I know it's not the be all and end all, but I ride a lot on my own, and it's nice to see if I'm improving. Editing the data is a real prick too.
From what I've read, it's when the start of the segment is too close to another part of the trail, ie in my case, as I was riding up, it set it off.
That's my main reason for looking at another device. I'd actually gone back to using My Tracks (google) as it seemed to fix it for one trail that this was happening constantly at Woodhill.

FYI Garmins, at least the older ones like the 500, really struggle under tree cover etc. My partner has a 500 and it's good on the road, but under the trees mountain biking my phone (Samsung Galaxy S3) is way more accurate. When I bother to get a Garmin I am gonna get a 510 or 520, will see if that is any better. I want to geek out with cadence and HR etc when I start training proper for CX next season.




As dave says, they suck with elevation if you are right by the coastline, something to do with how they use GPS to calculate elevation, so for example round the bays here fucks out and gives you exaggerated elevation, it's pretty accurate if you are away from coast and up in the hills though.

Yeah I'm using an S4 so can't imagine much changed. I don't really want to get a dedicated unit if it's no better.

mudguard wrote:Argh, what drives me nuts is how Strava (or likely my phone) sets off segments earlier. Today is a really good example. Rode in Rotorua, rode up to Billy T. Naturally had a rest about 50m above the entrance (get a little momentum). Work phone rang, so talked for 10 minutes. Checked fork air pressure blah blah, then into it.
20:39
Average 6kmh. Which was slower than my climb up!
I know it's not the be all and end all, but I ride a lot on my own, and it's nice to see if I'm improving. Editing the data is a real prick too.
From what I've read, it's when the start of the segment is too close to another part of the trail, ie in my case, as I was riding up, it set it off.
That's my main reason for looking at another device. I'd actually gone back to using My Tracks (google) as it seemed to fix it for one trail that this was happening constantly at Woodhill.

GPS inaccuracies and certain modes will make the start/stop points a bit fummy if they are not set a certain way down a trail. I get it really badly at the top of worleys where sometimes (usually when its cloudy) it thinks ive started going down so end up with a 50 second segment being 10 minutes etc depending on how long I fap at the top for.

There is some mode that the name escapes my mind now where the GPS unit is set to only send signals above/below certain speeds so you end up with a bunch of filtering going on. Its something that is stuck on with my S2 and you cant change but iirc its changeable on latter samsungs, I'll see if I can fish out what its called but there are a bunch of apps to change it for later phones.