For some reason, I can't seem to run the watchOS and the iOS app in parallel in their respective simulators.
If I build the apps with the watchOS scheme, then the iOS simulator starts up, but the app does not. If I want to run the (watchOS-scheme-compiled) iOS-app manually, it closes immediately. The same (but vice versa) happens when I chose the iOS scheme. In that case the watchOS app hangs during startup in the watchOS simulator.
How are we supposed to debug WatchConnectivity in that case? Or are my targets just messed up and it should work usually?
Ok, found it by now. I had missing some frameworks in the "Embedded binaries" section of my iOS app – this usually is only a problem when running on a device, but for some reason with watchOS they obviously change the way the respective iOS companion app gets started to facilitate installation of the watchOS extension. Anyways, it's good now.