The iPhone/iPad app "Mobile VOCALOID Editor" Ver.2.4.0 is now available on the App Store.
Applying this updater carries out the following updates:

Added Voicebanks (in-app purchases)

New Features
Added support for Chinese (Simplified and Traditional) as display languages in the application.
Bug fixes
Fixed other bugs, improved stability and performance.

For details on using Mobile VOCALOID Editor, please see the videos below.