I've been using the first beta for a day now, and it has been pretty good so far. But there are some bugs that I noticed, and some other things I hope could be improved upon.
I am using Watch4
Adaptive brightness isn't as accurate as it was on One UI Watch 4.5
Some apps take a bit longer to load
Camera Controller app takes a really long time to connect to phone
The animation for exiting the brightness menu in the quick panel is buggy
The haptic feedback for scrolling through the apps menu via touch bezel is glitched (the vibration feels like it plays twice, that's the best way I can describe it)
The haptic feedback sometimes plays twice when you reach the end of a page when scrolling
Haptic feedback sometimes doesn't play at all when you scroll and reach the end of a page (usually in the apps menu)
Some pages don't scroll smoothly when using the touch bezel to scroll
Battery widget tile will sometimes not show the battery of some devices
The watch battery drains a bit faster than normal
Some UI lags and stutters
Lag when using the back gesture (swipe right)
There may be some more bugs, but these are the ones I found. For the first beta build, it's been pretty good so far. Here are some features I would like to see implemented in One UI Watch 5.
Smoother, faster, and more consistent UI, no random lags or stutters
Improved animations
Better haptic feedback
Better messaging: sometimes RCS doesn't work when using the Messages app via watch
