I'm trying to install a clock face I made for the Versa 3 onto my Versa 4. On the watch you need to connect the charge cable (to the pc I assume). Then in watch settings there is a place to enable Developer Bridge/USB Debugging which I assume is how one installs an app for testing. This was via WIFI on the Versa 3. No WIFI on Versa 4. On the screen that reads "To connect to developer bridge, enable USB debugging" I select the switch to enable but selecting the "Yes" button just turns off the screen. It does not restart, and Fitbit Studio does not recognize the watch.
The same Yes/No dialog works for Factory Reset and Shutdown so I'm guessing the switch is just not hooked up correctly in the OS.
I've factory reset a couple of times, once connected via the PC app and not phone app. In that scenario the "Settings" button was greyed out so I couldn't even get to the step I am describing.
Is there some step I am missing? Is anyone else able to get USB debugging to work on this device?
The Fitbit Versa 3 SDK is not compatible with the newer Versa 4. Each watch has its own development kit with a special name that must be specified in the .json- Versa 3 is Atlas. If you take a program that works for one build you have to make the correct changes to the .json file, index, and widgets sections to make it work for another build. Follow official guide here: https://dev.fitbit.com/build/guides/migration/
That being said, you currently cannot download or create your own apps or clockfaces for Versa 4 or Sense 2 at all. It does not seem that Fitbit is going to continue allowing 3rd party developers to contribute, and it has no future plans to release an sdk for Sense 2 or Versa 4.
See forum discussion: https://community.fitbit.com/t5/SDK-Development/Sense-2-and-Versa-4-development/td-p/5245083
Moderators have suggested to leave a feedback vote here along with other users to ask Fitbit to add a Versa 2 and Sense sdk to Fitbit Studio.
https://community.fitbit.com/t5/Feature-Suggestions/3rd-Party-Apps-on-Sense-2-and-Versa-4/idi-p/5248677#comment-on-this