We haven't heard much from social gaming network Heyzap recently.

It's been working on building up its infrastructure in terms of supported games and audience, however.

And now a regulatory filing spotted by TheNextWeb has revealed a new funding round.

Having previously raised $3.7 million, Union Square Ventures and Qualcomm Ventures have dropped $4.3 million into the Series B round, bringing the company's total investment to just under $8 million.

Back to the future

Founded in 2009 in San Francisco, Heyzap runs its network - which operates much like OpenFeint did - across iOS and Android.

With over 9 million users, of which over 5 million are on Android, its SDK is integrated into over 2,500 games, providing achievements, online challenges and leaderboards.

You can find out more here.