World's Longest Ringtone Clocks In at Over an Hour For those of you who love to let your cellphones ring incessantly, never bothering to pick it up or let it go to voicemail, here's the world's longest mobile phone ringtone. The ringtone, supplied by Japanese company Dwango, lasts 61 minutes and 40 seconds and will be submitted for inclusion in the Guinness Book of Records. [PlusD via Textually]