I just uploaded my new “Nutty” (my last name means nut tree) Master Switch SmartApp. I have seen other similar apps but were mostly to complicated for what I needed. It does rely on the “On/Off Button Tile” device handler so you have to download/create from template this device in your device handlers. The app simply creates a virtual switch that will be on if any of the selected devices are on and off otherwise. Optionally turning on the master switch can turn on all or a subset of the linked switches. I use this to group all of my Harmony Hub activities into a single “switch” this allows me to use a single command to Alexa to turn off my TV no matter what activity is active and to have a single switch to turn off in various routines (Goodbye, Good Night, etc.). Let me know if this is helpful to anyone or if you experience any issues.
Not working for me, says unexpected error when I try to define a master switch in the app. Is this still working ?
It is working for me currently but I haven’t tried adding a new switch recently. Did you create the “On/Off Button Tile” device handler first?
I missed the DTH part, but anyway, my purpose was solved using the Alexa Switch DTH.