I have a GE enbrighten Add-On switch I never used as I have all Inovelli switches that I use together for my 3-ways. I do have 1 mechanical switch in my house, which is for my laundry room. Is there any way I can use this as a smart switch so I could turn it off from the Hubitat app or put a contact sensor on the laundry room door so that opening it will turn on the light?
sorry but no.
I myself bought one when I wasn't watchful being tricked by the lower price. It uses the traveler wire to communicate back to a true smart unit. It in and of itself is not smart.
So in short, no. You can't use an add-on switch as a primary smart switch. You do have options though. First one is to use a contact or motion sensor to detect door opening or movement and use that to trigger a smart bulb or something like this: Smart Switch Gen3 – ThirdReality with your existing physical switch to turn on and off a light. I have two of these. One controls a deck light and another controls a light in the water heater room. The deck light is controlled by a simple automation based on dusk to dawn. The water heater room light is controlled by a contact sensor on the door and turns on when the door is opened and off when the door is shut. For your case, you might need to add a delay to it turning off just in case the door is shut while someone is still inside. Or, you could use a motion sensor instead or with the contact sensor.
Anyway, there are ways to accomplish what you want to do at a lower cost than a fully-functional smart switch.
p.s. It is also available from Amazon: https://www.amazon.com/THIRDREALITY-Needed-Hub-Compatible-Assistant-SmartThings/dp/B0CRKNXQF2
I was pretty sure I couldn't do anything with it. It is still sealed in the box. I live in Winter Park, FL (Orlando suburb). If you (or anyone viewing this thread) want to pick it up from me or pay for the shipping I'd be happy to give it to you/send it to you.
The add-on switch is meant to sit with a matching master, so it usually will not act like a standalone smart switch on its own. For the laundry room, a contact sensor on the door is the cleaner path. Open turns the light on. Close (with a short delay) turns off only the light automation started, so a manual wall flip still wins.
Short write-up of that door-sensor lighting pattern: Turn lights on when a door opens | Home Automation Cookbook
Got it. Thanks.