Basically, pick up a cheap-■■■ 2gb android
https://www.amazon.co.uk/gp/aw/d/B0B2D5D5B3?psc=1&ref=ppx_pop_mob_b_asin_title
Install fully Kiosk Browser on it, and set a fixed ip.
Install the hubitat control driver and follow the awesome instructions
This is my hubitat device:
Simple webcore piston:
Note that for some reason, on my cheap box, there's a short pause and it can miss a beat. So I just start a phrase with an additional "ah...", to work around it. Not the end of the world.
Works lush.