Modu Innovative Mobile Phones World’s lightest mobile phone
Modu Mobiles recieved the Guinness World Record™ for the worlds lightest mobile phone because of the ultra low weight of 40.1 g (1.41 oz). Modu launched this mobile phone at the Mobile World Congress (MWC) event in spain in february 2008 and guiness world judges declared it as the lightest phone.Modu can be slipped into a wide variety of modu jackets – stylishly designed phone enclosures and modu mates – modu-enabled consumer electronic products. modu’s ecosystem offers boundless possibilities in a simple and affordable way.
As per SumitBahl :
Its a small phone which you can slip into many custom jackets, so, all your information like contacts, emails, notes etc wont be needed to move everytime you change a phone, it can be used independetly as well and in future all phones will have a slot to fit in modu.
Modu’s dimensions are 72.1 mm (2.8 inches) x 37.6 mm (1.4 inches) x 7.8 mm (0.3 inches). Throughout the design process of modu, the emphasis has been on keeping the phone small, light and compact in order that modu’s innovative approach could be realized. The result is a phone that is not only miniature, but also superbly designed and minimalist, whilst offering all the functions and capabilities of a normal-sized handset.
Check out ModuMobiles for complete collection of their innovative fancy mobile phones.

