In Xcode I see (no paired Apple Watch) even though the watch is paired and the watch's UDID is registered
I had paired my watch with a new phone and run in to this problem. I removed all files in ~/Library/Developer/Xcode/watchOS DeviceSupport/ and it solved it!
What worked for me is to go to the WatchKit App target and update the Team with the proper account. Once I did that, my device showed as eligible.
2021: All Quiet on the Western Front. It's been 4 years since my first response. I've now had a good run during December and the first 2 weeks of January. It was so good that I haven't closed the simulator a single time and kept my iPhone connected and never turned off my mac. This worked for 3 weeks but then my iPhone ended up in a boot loop and restoring fails. I bought a new iPhone and now I also can't really connect anymore. See y'all in 2022 :)
2020: At this point I can't even get WCSession to send data on the Simulators anymore. Message from Watch to iPhone with replyHandler works, message from iPhone to Watch fails with WCErrorCodeWatchAppNotInstalled. Every day starts with rebooting numerous times and deleting and setting up new iPhone + Watch combinations. Tried on a freshly installed macOS with my friend's devices and of course no luck. But it's clearly my fault. Submitting a bug report doesn't do anything as they only keep telling you that everything is working on their end and they will close this ticket now. I only wanted to help.
2019: New iPhone, even worse. Now, every single component in my development has changed since 2017 and I'm still stuck targeting the simulator with every build. Apple, why?
2018 II: nothing works for me anymore. Contacted Apple loads of times and Apple Watch seems to have moved to Playground's neighborhood as it's just loading/running but never really running. Bought a second Mac, new project, nothing works. Sad.
2018: The last couple of days I have been really successful doing the following:
On your iPhone:
- turn off wifi
- turn off bluetooth
- turn on wifi
- turn on bluetooth
On your Watch:
- turn on flight mode
- deactivate flight mode
Most of the times it didn't take longer than 30 seconds to get the connection back on track. I think it's the "Watch flight mode"-thing but I never change a (somewhat) running system so this will be my procedure from now on. My 2017-reply still seems to be of help to some people:
2017: If it SOMETIMES shows, and often doesn't, it might be due to the fact that you closed iTunes
I noticed what I often did after reconnecting: closing iTunes. Immediately, the watch turned to be "unpaired". Reconnecting the USB cable but leaving iTunes open has helped me since.