First hand on the mobile phone topic,
our B737 experienced a dutch roll (uncontrollable roll side ways like a feather floating to earth), aircraft uncontrollable flight landed at nearest port, pax unloaded, aircraft checked by engineers, find nothing, test flight aircraft, no abnormalities. pax moved on by other aircraft. Only finding, pax with mobile telephone on boarding asked to turn off (had it in his ear) asked to turn off again, finally turned off - we think....... no other explanation for incident. Airline now has strong policy on mobile phones and other electronic equipment.