Just an relatively uninterested third party comment, but I was having a problem with something on the iPhone after an update, and I tried 'everything' to get it solved. I think I even posted a rant here.
BUT THEN...
I rebooted my iPhone, and problem solved... I felt silly, and then thought that I have gotten used to, now, installing updates and not rebooting, and maybe this would be fixed with a reboot, and maybe not, but I'll have to remind myself that in the future, rebooting the darn thing should be one of the first things I do.
Oh, I remember, it was with the Nike+ app. I couldn't get it to work to save my butt, and I was mystified, pissed, and 'not happy'. Plus getting ready to travel, and wanted to pop the latest wanderings into the Nike+ ether, and well, not feeling the love. A reboot, and things worked again. YMMV...
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I have a problem with the cycling. After a bike ride it shows I climbed a bunch of stairs. I rode 26 miles yesterday, the phone said I climbed 14 flights of steps and traveled 1.4 miles. The cycling distance is fed into Health via Strava and it did this correctly for my cycling distance and time but the data collected from the phone was not right. It has an issue with knowing that I went for a ride and excluding the data during that time. It should see that I was not walking based on the fact that it has access to ride data, the day/time and speed.
Oh... That sucks. And I'm not being flippant either.
I am using a Garmin edge 810 for my biking telemetry. Call me old fashioned, many do, but I'd rather have a dedicated device log everything than rely on an app. Although, my Edge did bite me, pretty hard too. There was a bug in one of their firmware versions that did not save the ride telemetry between rides if you didn't synch it before turning it off. Oh, and the Garmin app wouldn't synch the data without spending a frustrating amount of time, and having a lot of luck, but they fixed the saving the data problem... I 'lost' some really awesome rides that I'd have liked to have kept the data from, but that's life I guess.
I'm looking seriously at getting the Garmin fenix 3 now instead of an Apple Watch, because it's capable of doing all of the telemetry I think I'd ever need. (And the Apple Watch doesn't do ANT+, AFAIK)
Plus I found Strava as being too tied to one brand of sensor, and the Garmin works, so far, with everything I've thrown at it. It works with the DuoTrap on my Trek, and it's one less thing that I have to futz with.
Climb on, hold on, and go. Simple works...