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Old September 15th 16, 02:32 PM posted to sci.geo.satellite-nav
Alan Browne
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Posts: 1,339
Default Puzzling change in trackpoint rate

On 2016-09-14 15:35, Terry Pinnell wrote:
Seems fairly quiet here but I'm hoping that one of the resident
experts can help me get to the bottom of some odd behaviour please.
I've tried several GPS, iPhone and iPad forums but still have no
satisfactory resolution.

I can't understand why my iPhone 6S+ recently started recording many
more trackpoints than previously:

Most of those have used the Memory-Map iOS app on my iPhone (plus a
few on my iPad) but I get the same averages with another app, Pocket
Earth. So it's app-independent, purely down to the iPhone. Here's a
track I recorded today (with Pocket Earth), which (unlike the examples
in my table, which were all walking) include sections of waiting and
bus riding too.

I'm still not sure if it's a good or bad thing! Unlike dedicated
devices, on this 128 GB iPhone I have no shortage of storage space. So
maybe I should be celebrating the unexpected availability of vast
numbers of trackpoints, instead of fretting about it!

But ... why would the rate have *changed* so greatly around early

Perhaps it updates less often when there is poor quality in the position
solution. Where do you have the phone when you're recording such
tracks? (pocket?). When the points were more numerous did you have it
in a better position? Was it hilly or urban canyons? (The later should
have good cell aiding, however).

Even sat geometry could have an impact at the time that you're recording
on the position quality.

Just a guess.

She hummed to herself because she was an unrivaled botcher of lyrics.
-Nick (Gone Girl), Gillian Flynn.