At the recent KDDI au Design Project in Japan, au Design Project x Yamaha created concepts that challenges the meaning of "music phones" in the industry's lingo. You see, unlike the conventional mobile phone that focuses on its media player functionality, the concepts are actually cell phones and musical instruments in one.

Luckily, Trends in Japan was there to cover the presentation of the prototypes.

Name: Trio in your hand
A phone which flips open, revealing a sampler and scratch pad for DJs on the go

Hit the jump for five more prototypes.

Name: Band in my pocket
Comes with numerous accessories that turns the the device into different types of wind instruments such as trumpets and harmonicas

Name: Box to play
Is a musical toy which could be used as a scratch pad or a synthesizer that folds into a cube.

Name: Key to touch
A cell phone that folds out into a keyboard.

Name: Sticks in the air
Cell phones which can be unfolded to reveal drumstricks equipped with sensors to produce beats.

Name: Strings for fingers
A cell phone which has an integrated small string instrument.

For pictures of the prototypes during the presentation and videos of how they work, check out kilian-nakamura.com.