Late this evening, i was listening to live ATC from Tunis ACC then the controller asked the pilot of a Biz jet registered in Turkey (callsign was Tango Charlie...) to switch on his mobile phone, in the cockpit, in the air, whilst climbing FL370, on request from his company which was trying to call him ! The pilot said he was unable to phone, but the company insisted. The controller said " they want to contact you regarding restrictions overflying i don't know which country airspace".
I know you can now phone during flight but within specially fitted airplanes.
Is it safe to use his tiny usual mobile phone in flight ?!