First of all, welcome to this place!
Do you enable airplane mode when flying a general aviation aircraft?
Negative. My plane doesn't even have such a switch - though, if there were one, I think I would prefer "airplane mode" over "coffeemaker mode"
Seriously: don't worry about all those gizmo's! Keep that "smart"phone as far away as you can, there's a plethora of other things to keep your attention going. Learn to fly the plane with as little "auxiliaries" as you can - your instructor might well cover all your instruments one day, with a sheet of paper or so. It happened to me, and did me a power of good!