I find this approach hugely frustrating. My Fenix3 wont even connect to the app whilst the servers are down. I use the f3 to enable the 'smart' unlock on my nexus 5 - but this doesn't work whilst the device is unable to connect. Why on earth have Garmin developed an app that is so reliant on a connection to the backend ? I can understand the need for the servers to be up in order to deliver the activity feed, look at old activities, download ConnectIQ stuff etc. However, surely there is lots that can be done without a connection to the backend ? Even very very basics like enabling the sync of an activity to the phone for local analysis - and then syncing this with the servers at a later time. Seems utter stupidity to absolutely require the app to connect to the garmin servers before it can be used.
Garmin had a banner saying they were going to do maintenance yesterday. It's obviously taking longer than they expected.
https://connect.garmin.com/en-US/status