Running on iphone same assimulator?

Hi,


I'm fairly new to Swift and Xcode, but have come so far that I have managed to create my first app. It's a somewhat complicated app with a few storyboards, 10-15 VC's. Over the last weeks I have deployed the app to my iPhone and after a few days of testing, the app usually crashes, making it stop loading again unntil I rebuild it from Xcode. Yesterday I added Firebase to my app and after deploying it to my iPhone again, I created a FB record and changed another one. Now, that record won't load from FB even If i close the app on my iPhone and start it again. Running it in the simulator, It fetches the record just fine - and that without any changes to code. Creating a new record today on my iPhone works, and it shows in FB, but not the changed one from yesterday.


So - is running the app on my phone not as stable as using the simulator? I haven't come that far as learing about app life cycle management, so I might have missed some basics regarding that...?