RFM Radio popped up when I searched on f-droid (IzzyOnDroid) just there, says it’s incompatible with my version of Android and it requires root but it does actually use FM radio.

It is wizardry right enough - electricity goes in, magic occurs,l and machine goes ping

It’s definitely not as exciting as it sounds. It applies a large current through some graphite rods which causes the carbon to evaporate & deposit on a sample sat underneath. It’s used to coat electrically insulating samples with a conductive layer of carbon for electron microscopy.

We have a carbon evaporator that runs linux