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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Time on iPhones
From: Peter Monta
Date: 2013 Nov 2, 15:19 -0700
The phones don't normally run their GPS receivers continuously, but even a few seconds per day would be plenty to keep the clock in trim.
Cheers,
Peter
From: Peter Monta
Date: 2013 Nov 2, 15:19 -0700
Hi Lu,
I don't know in detail the clock system on iPhone or Android; it is annoying that it still isn't perfect, especially since the technology is so mature. The "Emerald Time" app on iPhone/iPad/iOS uses NTP, the Network Time Protocol, obtained from public Internet sources, and is trustworthy to maybe 50-100 ms over cellphone channels (it's much better than this over wired networks, since they don't have any nasty asymmetries). It also shows the offset against the phone's normal time, usually a few seconds on my phone. Android has the similar ClockSync app; maybe the newer builds are native NTP now.Cheers,
Peter