Fitbit won't Sync - check the time on your device.

[JudeF]

My wife (using her account here) had an issue with fitbit not synching properly the last few days.

TLDR version: if the time is out on your device, authentication will fail during the retrieval phase. Symptoms will be part communication to your fitbit (battery levels), and the sync will cut off about 1/3 of the way through. Switching the ipad over to manual time, then setting the time resolved the issue.

She called fitbit support which did the usual script, but no actual troubleshooting. Their opinion was that our internet sucked.

I got involved - as a network engineer I tried to get some technical information - what the app was trying to communicate to so I could check the communications side of things, but fitbit wouldn't help with that information citing 'security'. I pointed out this was misguided because it would take just a little bit of effort to determine that myself (dns request logs and network activitity - the kind of thing any competent tech can do) and suggested fitbit put up at least a simple webpage on the host so that people could open a web browser to confirm connectivity.

After doing some analysis it became apparent that the fitbit transfers data through the app to fitbit without authentication, but that the app requires auth to retrieve data.

Because communication was working one way, it wasn't connectivity. Time is the other critical part of authentication issues so I checked out the time on the ipad and it was out about 5-6 minutes. That's too far for authentication to work.

The ipad was on 'automatic' for time - so it looks like whatever NTP servers the apple devices are synching to are out of whack for at least the one being used for her device. Switching the ipad over to manual time, then setting the time resolved the issue.

[MariamV]

Welcome to the Fitbit family @JudeF! It's lovely to have you here.  Thanks a million for pointing out what worked out for you and your wife. I'm sure this will come in handy to other users also experiencing syncing issues with their trackers and the iOS app. I'm stunned by how clever the solution was, it was amazing! Thanks again for helping us out here in the Community! I really hope to see around more often.  The Community is nourished by users like you, willing to share their knowledge and experience so we can all learn from each other! Feel free to post back.