I for the life of me can't see how these devices effect any A/C system
Both of the incidents that I experienced (3 years apart & different airplanes) involved the autopilot inputting rapid aileron oscillations - the second one (on descent into Singapore) was very rough and required prompt disengagement of the autopilot. Two LAME's who were paxing on the flight commented later, on how severe the rippling of the wing upper surface was.
The use of the mobile phone (on both occasions) occurred soon after a PA was made advising the pax of an ATC delay before landing.