iPhone geocaching

[+bonnie_croft]

Hi! I have a question regarding the iPhone for GPS. I have a 5, I'm not sure if it makes a difference. Anyways, I have started placing my own geocaches and am having issues with the co ordinates. It seems to be when I'm under trees. There's always a 5 m difference because I use the geocaching app. Just wondering what I can do to make it more accurate? Is there an app that would give better readings? Also, I have a garmin nuvee, would it make a difference if I used it instead of my phone? Any advice would be appreciated. Thanks!

[+Bear and Ragged]

App Perfect Mark gets a lot of mentions. May be worth looking at.

 

Best tip is: Take your time getting the coordinates, give the device a chance to settle.

Once you have a set of coordinates walk away, and see if they get you back to the same spot.

 

Be aware that two -or more- devices will never agree!

[+Lieblweb]

Use both the phone & the Nuvi.

 

When we first started, we used the 'Perfect Mark' App. You can take several samples and it'll average them for you. I would give the phone at least 10-15 minutes to settle before grabbing your first sample. Then, walk away from the area about 50feet and come back to the area, give it time to settle, and take another sample. Do this several times walking in different directions.

 

After fiddling around with the phone samples, I got the NUVI out and took several samples with that. The Nuvi won't average the data, but you can collect as many data points as you want and compare them with the phone.

 

If your data is drastically different between the Phone and the Nuvi.... I would highly recommend going back another day and taking more samples. When your data is close between the phone/Nuvi, consider it good enough to submit. Submit the cache and wait..... You'll get enough feedback from finders - whether or not your data needs readjusted.

[+user13371]

With iOS 6 (which the OP's iPhone 5 has, and many older iPhone/iPads might have),Apple changed how positions are reported, in a way that will be really poor for geocaching.

 

If you are standing still and have a perfect signal and there are no roadways nearby, it will give you reasonable coordinates. If you have less than a perfect signal, or you're moving at any rate faster than a slow walk - the location services will access Apple's mapping database and try to snap your position to the nearest road. Absent any roads nearby, the position pointer will wander quite a bit more than it did in iOS 5. It will frequently do this even if the application you are using is NOT Apple's Map program.

 

Internally, this is default behaviour of Apple's location services. there are supposedly ways to program an app to not do this. But I haven't found any that reliably ignore Apple's road maps.

Edited August 5, 2013 by user13371

[+Red90]

Is this the same when using it with a BT GPS? I have a 4S with a Garmin GLO and have done a dozen caches with it and the Groundspeak app. I never noticed any strange locking to roads with this setup.

[+user13371]

Rec90, that's a good question - I don't know the answer, either. Lots of variables: You may just not have triggered the kind of conditions I have, or an external GPS might not have to same issue, or maybe it only happens on newer iPhone / iPad devices (not older ones upgraded to iOS 6). But I'm not makin it up and I'm not the first to observe this. Google IOS6 snap to road

 

There's an easy test. Run Apple Map while riding the train and watch the little blue dot. You could try that with both the 4S internal GPS and your GLO to see if there's a difference.

 

---

Edit to add: Another variable I thought after looking at your profile. Apple might not have snap-to-road data in UK.

Edited August 7, 2013 by user13371

[+JingleBella]

Although I've heard people some Garmin Nuvi's work, I've tried it with my Garmin three different times and had to no luck. Was trying to use it as a second source to my iPhone.

 

I have two additional apps that I use when placing geocaches (or entering puzzle coords). One is called Free GPS, the other ViewRanger. Free GPS is fairly user friendly. But you definitely have to take the coordinates, walk away, navigate back to the coords and continue this until you get within a few feet of wherever you placed it. It's a pain in the butt but it's better than having people upset that your cache is off by 60 feet. I know I have a couple of mine to fix where I only walked back twice when I should have re-checked them 3 or 4 times. Keep in mind though each GPS functions differently. I've had it where two different cachers who I know use good handheld GPS units, one will say the coords were within a couple feet, the other will say it was 20 feet off. So many factors come into play with GPS signals

 

[Edit for spelling error.]

Edited August 7, 2013 by JingleBella

[+TombRaid3r]

I've had pretty good luck using my iPhone 5 and the official geo app. I got the coordinates at the site, then when I got home, I typed them into google earth. The position that came up on the google map was extremely close to where I really was.

 

You say you're getting 5 meter accuracy. That's actually pretty decent. From what I've read, that's within the normal margin of error for most GPSr's.

[+Ben-n-dad]

I've had the same issues with iPhone 5. Out of 4 caches, 2 have been accurate and one was off by about 25'. The 4th was posted today so I'll find out soon. I just received a Magellan exploirist GC today. I went to the nearest cache and between the 2 units there was about a 5' difference. I'm gonna roll with the Magellan unit for a few days to see how it performs. I'd like to use the iPhone to get me there and pinpoint with the Magellan. We'll see.

[+thebruce0]

If you have a handheld, use that, at the very least alongside the phone if you're not confident in its reporting.

 

Walk around gz a bit. I find sometimes that if the phone thinks its coordinates are good, it may not update unless you move. 'accuracy' may not get better than 5m especially under trees, but it's much easier to gauge how accurate the estimate is if you watch your location on the map (you natural have more doubt seeing numbers with a +/- than seeing where the center of the estimate is in relation to nearby landmarks; whether on satellite (which can be misaligned) or road view)

 

I haven't tried that Perfect Mark app, but it sounds useful. Again, useful if the coordinate reporting doesn't 'stall' from lack of movement.

 

Don't forget - if you use the handheld to get gps coordinates, do the very same thing! It's always good practice regardless of device to give the signal time to settle, average, walk around gz both for motion and to provide a physical range for averaging as well.

(I've seen groups of cachers wandering around gz searching for a cache, each reporting different accuracies at different distances - there's no guarantee your device will be 100% accurate, whatever device it is - just do your best to get the most accurate reading you're comfortable with).

 

Oh also! If you have friends who can help get gps readings, use them too, if you're still unsatisfied.

Edited August 14, 2013 by thebruce0