VocaloWitter, previously known as "i-Vocaloidt" is the portable version of the software released for iPhone
While this version has limited capabilities, but at the price ¥350 for the iPhone has made this the cheapest version of the Vocaloid software currently on sale. Currently, this version of the software has only been released in Japanese and there is no known details on if a English version will be released or if any other Vocaloids will be released on this format for that matter. Those wishing to purchase this software must also have a Japanese chip on their iPhone to use this software.
VY2 was due for release on this format before the summer, VY2's version would have adjusted the VY1 version for compatibility and performance reasons. However, it has never been released.