It seems that the mobile app has been updated to include a timeout when loading pages, which causes CoRE to become unavailable. Whenever I load CoRE to edit it takes 10-15seconds sometimes because I have 35+ pistons. it seems that the new version of smartthings times out after 10 seconds of trying to load the smartapps settings.
I was able to revert to 2.3.1 and am able to access CoRE…
I have the same issues even getting to Automations | SmartApps let alone CoRE afterwards. Didn’t report it yet as I figured there many with the same issue on Android Marshmallow and Nougat.
@ady624 just merged a patch that will speed up the load time of initial CoRE page so that users with more pistons won’t be affected by the reduced timeout window. Feel free to reach out to me if you are still experiencing issues after updating CoRE
That fixed loading, but still having timeouts in the app, when I create or try to modify pistons many pages will say “there was a problem processing your request.” or “unable to save”… etc reverting to the old app fixed the issue and I was able to create/modify.