The Prota microbot @Hilly_2015 linked to is made for just this purpose, a “robot finger.” I was just given a set of three at Christmas so I’m just beginning to set them up, but I’m going to use one on a blender that has a button that is particularly difficult for me to press (I’m quadriparetic).
This is an expensive and kind of weird option, but it definitely solves use cases that other options don’t. You need the $99 prota bridge if you want it to integrate with SmartThings, which you do through IFTTT. Then each Microbot is $49. But it works well when you have a device that you are really happy with except it needs a physical button push.
