I just wanted to share my experience of developing for Tizen using Xamarin, since its been pretty positive.
Although my early experience of using the Tizen tooling was a little rough, things have got a lot better.
The debugger works for me, in that I can set breakpoints and they are triggered. I generally run without the debugger though, and use logging to trace the flow of my app. This is a batch script I run in a separate window to the IDE ("viac" is the log tag I use when logging):
sdb dlog -c cls sdb dlog viac:D"
I was able to take an existing Xamarin Forms app, and bring it over to Tizen with minimal effort. The nature of my app means that there is some platform-specific code (low level audio, and http/2 etc.), but my .NetStandard 2.0 share code worked fine, and although I didn't reuse all my views, I did reuse my view-models. I used the watch-specific forms pages and controls that Samsung provide, to get things like the bezel working, binding them to my existing view-models.
I ran a long beta which gave me great feedback. My app is a standalone implementation of Amazon Alexa (Voice in a Can) that runs on Samsung Tizen 4.0 Watches. During the beta Samsung rolled out Tizen 4.0 to S3 and Gear Sport watches which massively increased the market for my app, which was an unexpected plus.
I'm an independent developer and in no way connected with Samsung ... developing and releasing non-trivial apps for Tizen is possible, and in my experience at least, not that difficult, especially if you've developed for Xamarin/.NET in the past.
Damian
https://damian.fyi