Mobile Demand Side Platform (DSP) StrikeAd has secured the second round of its Series A funding from three US investors. The company has also moved its headquarters to a new office on Fifth Avenue in the Flatiron District of New York City, where CEO Alex Rahaman has relocated from London to lead the firm’s expansion in the US.

After receiving $2m in the first round of its Series A funding from European venture capital firm DFJ Esprit including follow-on from German ad tech entrepreneur and seed investor Thomas Falk of eValue, StrikeAd has secured an additional $500,000 to close the round. This funding has come from three West Coast investors: venture capital firms SoftTech VC and Siemer Ventures, as well as angel investor Gil Elbaz, co-founder of Applied Semantics. StrikeAd says the additional capital will be used to fund its expansion into the US.

“Mobile usage is booming and browsing the internet on multiple mobile devices is the future,” says  StrikeAd CEO and founder, Alex Rahaman. “The problem today is that buying mobile advertising is far too difficult and murky. This investment fromSoftTech VC, Siemer Ventures and Gil Elbaz will help us to capitalize on the huge market opportunity for mobile advertising technology that delivers far better transparency, information and returns in this new channel.”

As the world’s first mobile DSP, StrikeAd aims to simplify the complex, fast-changing mobile marketplace by creating and managing mobile advertising campaigns easily and effectively for advertisers. The company offers agencies and marketers a single point of access mobile web and in-app ad inventory, both in the US and internationally.