I went to look for maps for Garry's Mod and saw this thing's workshop page...
https://store.steampowered.com/app/977920/BalsaModelFlight_Simulator/
...I don't think it'll be able to do everything SP can when it's finished (I don't think it'll ever come to mobile at all).
Thoughts?
Oh boy, Jundroo hit the KSP dev team hard with SR2 and this is their answer... Andrew, you gotta rack up your game quickly