In case you've never seen the lionchief app. This is an old iPhone 6+ with no sim card that I use on wifi only. The screen is trashed but I'm too cheap to fix it. The smoke unit on this PE is the piston type, and it seems you have to run the train pretty fast to get it to puff smoke. Too fast for the O31 curves on my xmas layout I think. YMMV. Anyway, the bluetooth app really works pretty good. Lionel lionchief Polar Express w/Bluetooth