I’m on the new app and always have been.
this evening, after things working fine for days, suddenly my SmartThings devices (and hub) are unresponsive. The app doesn’t even show any status associated with the device, and clicking on the device or hub does nothing.
SmartThings Status is “operational”
Reboot my cable modem (via xfinity) and mesh routers (via eero app)
rebooted hub (power cord).
Still nothing.
Any ideas??
I’m in the same boat for what it’s worth. I’m thinking server maintenance or an as of yet unreported issue is going on. ~2am UTC is typical for North America server maintenance windows.
This app is a crowd sourced problem detector, seems like there are a few others having issues right now:
Cool, thanks. I feel better now and can go to sleep… if I can only figure out how to turn off the lights using “switches”… maybe I can find a demo video on youtube… 
My one SmartThings button is still working. I’m guessing it operates locally on the hub.
Yeah same exact issue here too…everything has been working perfectly for weeks…only used new app since setting up and now when I open app everything is offline or not responding.
When I try logging into https://account.smartthings.com it redirects me to a different server than usual and there are no hubs, no devices, no apps nothing setup at all there…it’s like all my stuff is gone.
Redirects me to somewhere else instead of the usual https://graph-ap02-apnortheast2.api.smartthings.com/
I also assumed it was something to do with a server being down etc, but it’s been over 24 hours now…sure it will come right soon.
Just made some progress and got everything working again. I had restarted the hub multiple times, but then read somewhere that I should try restarting it via the IDE web interface and not just turning off the power to it and low and behold everything came back online after the restart…
I’m all up and running now after nearly a week of being down after something happening on Sep 9th ish kinda time… no idea if it will help you and I was skeptical that it would make an difference, but clearly it doesn’t something different.