Mobile phones absolutely do interfere with aeroplane systems. You know how your radio goes dit dit-dit dit when you change cell towers or receive a message? Hap

Mobile phones absolutely do interfere with aeroplane systems. You know how your radio goes dit dit-dit dit when you change cell towers or receive a message? Happens with aircraft radios too. Extremely annoying when your passenger ignores your request to turn off their phone. VOR, ADF, NDB and ILS also all use radio waves and could therefore also be subject to interference.