So I have had several SmartApps setup and they seem to be running and show in the IDE. Few days ago I reset my android phone and reinstalled everything. Now in SmartThings, the “hamburger” menu doesn’t show SmartApps (I think it was here, correct?). If I go intoMarketplace, SmartApps, MyApps, I can see them. However, Core for one, acts weird, it is stuck editing one of my pistons and doesn’t show the list of all pistons. I make a minor edit to the time, hit done, it goes back to list of MyApps, not list of pistons in core.
Can’t speak to your CoRe issue but the SmartApps are no longer in the hamburger menu. They were moved to “Automations” at the bottom navbar of the App. This was done with the last App update a week or so ago.
You probably never updated the app but received the new one when you reinstalled.