Like you, I just use the EV Connect app to start/stop climate control. I just looked at all of the menu items available for my 2015--there is one to start charging, but I don't see one to stop charging. The only reason that I can think of to start charging remotely is if you have a timer set and plug the car in outside the allowable charging time window so the car is waiting to charge. In that case, I think you could send a charge start command to start charging immediately. Hopefully, someone will reply if my interpretation is not correct.
Silver LEAF 2011 SL rear ended (totaled) by in-attentive driver 1/4/2015 at 50,422 miles
Silver LEAF 2015 SL purchased 2/7/2015