stray points when Quik Capturing polygons

[BertKraan1]

A collegue used my newly developed solution to capture some vegetation in polygons. I noticed some stray points way out of the place where he really was:

Nothing that can't be fixed but I wonder, is there some setting that I need to set/fix/tweak?

He's using an iOS device, iPhone 7 or 8 with a current OS.

So what could have induced this: Internal gps receiver and it was rainy weather. Next time I'll lend him an external gnss (EOS Arrow 100) to see if it persists.

regards,

Bert

[JohannesLindner]

In my experience, that is the phone's GPS just spazzing out at times. I have the same problem with geotagged photos. everything looks great, then I see a few photos way off from the others, all on the same spot. The photos I made a minute later are all right again.

A "fix" I found for this is checking my position in the phone's map app from time to time. Especially when I changed locations in a mayor way, like driving to the next capture site, I wait until my position stays constant in the map app.

[Mandy_Li · Accepted solution]

Hi @BertKraan1 The 'jumpy' points (spikes) are likely to happen when the device has a poor cellular or wifi signal, as the location is estimated from sources like GPS satellites, the closest Wi-Fi networks, and nearby cell towers. We've seen this more often on Android devices than iOS devices, but feel free to let us know if you persistently see this issue during future testing. 

A dedicated external GPS receiver definitely gives you higher location accuracy and provides a location fix faster, than the built-in GPS on the device. 

You could take a look at "Horizontal accuracy" in project Settings. This will force the app to only accept points that meet the required horizontal accuracy. However, it is not a solution for the spikes issue above, as sometimes the spiky point will have good horizontal accuracy, even though they fell at the wrong location.