Yahoo! (NASDAQ:YHOO) Japan and Gree announced Monday that they will establish GxYz, a joint venture to develop and operate social games for smartphones. The agreement has been official since Nov. 2012. 

Through GxYz, the two companies hope to leverage their respective strengths and create a new entertainment business capitalizing on the growth of smartphones. While Yahoo! Japan can offer user acquisition capabilities, Gree's expertise is in gaming development and operations.

Yahoo! Japan -- one of Japan's largest Internet media portals and one of that country's largest social networking services -- and Gree have a history of working together. Yahoo! Japan's mobile page has already featured links to Gree's social games. Currently, they are jointly supporting the Tokyo 2020 Olympics and Paralympic Bid Promotion.