Swipe right / left to change the color.
Swipe up / down to change the brightness.
'Room Light' - https://play.google.com/store/apps/details?id=air.com.bfrontier.flex.SleepLight
Disclaimer
This app is provided "as is", without warranty of any kind.
Your use of the app is at your own risk.
LiveWare™ extension for SmartWatch