iPhone Strava app data loss

Following a 7-day break from running following the Lake Chabois 30 km trail race, which went extremely well for me, it was back out there again today. I did a relatively short run, recorded by the Strava app at 12.8 km, but actually longer. I've had really poor luck since upgrading my phone from the venerable, battery-starved HTC Incredible to state-of-the-art iPhone 5S. The Incredible has extremely solid GPS tracking, so I expected at least as good from the iPhone.

But I get these weird data drops with the iPhone. Here's my run today:

Running on Howard I lost GPS, apparently semi-permanently, until I looked at my phone and brought up the app and saw the distance jump by 4 km within 2 seconds of bringing the app onto the screen.

Here's another, a run from before the race:

I lost signal on the way out, only getting recording again when I brought the phone out at the turnaround near Sutro Baths to check my distance.

Another one: I lost signal when I was in a food store, and the entire end of the run was lost:

It seems when the app gets into trouble it basically gives up, going into some sort of sleep mode, until explicitly revived at which point it tries to find GPS again.

One positive from today's run: I came across the cool highwheel tricycle replica:

bicycle

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