Hi guys, I am looking for a strong, tough, rugged cell phone which can sustain in any condition. I want to gift this phone to my father who works in a plant. He has a history of literally destroying almost 9 of his previous cell phones either by dropping it on hard cement floor or down a flight of stairs. Therefore I need a phone that has the ability to sustain such hard situations. It needs to be an unlocked GSM cell phone. Can anyone please suggest me a sturdy cell phone?