JManga is an official online manga portal site created by 39 Japanese publishers and launched on August 17, 2011. It is available worldwide.
Update: On March 14, 2013, JManga suddenly announced that they would be ceasing all of their online publications as of May 30, 2013. The exact reason for this is currently unknown.
At the time of the announcement, users could already no longer purchase points for use in purchasing their serializations. Refunds for unused points will be issued to all subscribers in the form of Amazon.com gift cards.