GREE, Inc., or GREE for short, is the company (and Social Media Service), alongside Square Enix, that created The World Ends With You Live Remix.
About GREE Edit
GREE was initially available for PC users only, but as the market demand of iOS and Android became larger, they soon moved to those platforms.
GREE, Inc. bought out the Mobile Gaming Platform, OpenFeint, for over 104 Million US Dollars. The service was then discontinued, and replaced with GREE.
GREE Corp - http://gree-corp.com/
GREE (America)- http://product.gree.net/us/en