is a concept of a modular phone which is both a standalone phone and also the core of a range of variety of terminal devices.
modu contains not only a slot for a SIM card, but also all the transmission technology needed for a mobile device to work. It contains another storage area of 1GB or more, and also a battery and input and output peripherals that enable it to work as a basic phone for voice calls, messages, and using the stored data, such as the music files.
As a module, it can be slipped into a variety of terminal devices (called modu jackets and modu mates) to create a new look and provide added functionality. In other words, a terminal device developer can build a customized terminal without the design and development of a radio module, and users can change to a different radio module "modu without changing the terminal itself.