Todacell investors have pumped another $2 million into New York City-based mobile advertising network company as it aims to double its headcount by expanding its London office and opening a new office in Berlin.

In addition, Todacell is today announcing that it has hired Mark Lehmann, previously VP Web & Mobile Marketing at Universal Music Group / Island Def Jam, as CEO.

The company’s founder, Moshe Vaknin, has stepped down as chief exec and now serves as a board member and strategic advisor for Todacell.

Todacell aims to solve the problem of excess mobile ad inventory caused by the surges in smartphone and tablet penetration in markets worldwide by utilizing proprietary optimization technology.

Basically, the technology enables agencies and marketers to optimize mobile marketing campaigns and lower costs by making sure they reach the right users.

The additional $2 million in funding comes from AfterDox, a group of investors from telephony billing solutions provider Amdocs, as well as private investors. Todacell has raised $4.35 million from the group to date.

Founded in March 2007, Todacell is headquartered in NYC with R&D in Israel.