I bought a piece of 1.5 inch stiff foam to try to fix a sag in a bed. It didn’t work but having that thick piece of solid foam around has been a life saver.
Need something flat to put a laptop on? Throw it on the foam. Going to be doing something that requires you to be on your knees for a while? Get the foam!
It went from stupid purchase to something I’d gladly replace if it broke.
In my experience, you need the app if you use a valved filter (i.e. Clever Dripper) as being a little cooler, the Ember mug doesn’t trigger the heating, and you have to tell the app to increase the temperature manually until it realises there’s a hot drink in there.