My C-7 HE hub is running Platform version 2.3.9.174 and I am running the current version of the new Android app on my up-to-date Pixel 8 Pro.
With the previous Android app version of Hubitat I could display a widget of a button on my home screen, but now with the new Android app the only widget choice I have is to display dimmers, when the list actually displays any dimmers.
IFTTT has a Hubitat integration. You can create an applet that has a button press that can control any Hubitat device and then add the button to your home screen.