Joining a parade of startups, MocoSpace launched a mobile, browser-based social games platform today.

While many platforms have been launched for social games recently, the Boston-based company is bucking a trend with its approach: Rather than helping build native apps specific to a smartphone operating system, MocoSpace lets developers build Web-based apps.

MocoSpace has been in operation for several years and has 12 million users for its mobile social network. Now, like social networks such as Hi5, it is shifting to what is hot with a new focus on games.

The MocoSpace Games platform will use the company’s virtual currency, Moco Gold, to deliver social experiences in games developed by others. MocoSpace already has a number of single-player games that are being played a million times a month, but it will debut its first social title in July.

Justin Siegel, chief executive of MocoSpace, said the plan is to bring the virality of Facebook games to the mobile Web via a browser-based smartphone platform. The company will launch its own new games and will enable third-party developers to use its platform as well.

MocoSpace launched in 2005 and is backed by $7 million in funding from General Catalyst. The company said it is focusing on games on mobile browsers so that it can reach the widest possible audiences. Rivals include MySpace Mobile, Facebook, Aurora Feint, Ngcomo, Scoreloop, and PapayaMobile. The latter just launched its social mobile game platform Thursday as well.

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