Free cross-platform app store GetJar is growing fast: earlier in June, it announced it had hosted one billion downloads.

Now it plans even faster expansion as it's closed its second round of funding, gaining $11 million from initial investor Accel Partners.

"GetJar is operating in a unique space, which is filling up with a lot of players, but we're not sitting on our laurels. With this investment, we're going out to play offensively," says Patrick Mork, GetJar's veep of marketing.

"We've been growing steadily in terms of headcount, revenue and downloads. We're also profitable, so this investment is a case of speeding up our growth. Using it we can open up offices in new countries, improve our product, as well as release on-device clients."

London calling

The UK will be a particular geographic focus for GetJar, where the company is currently hiring sales and marketing and technical staff.

"It's the most important market for us after the US," Mork explains.

The investment takes GetJar's total investment from Accel to $17 million.

"There was a crazy demand from investors but as it happened, the best deal we were offered came from Accel Partners," Mork reveals. "If the wheel's not broke, why fix it?"

"We doubled down in this Series B due to GetJar’s momentum as the leading open platform in the mobile apps space," says Accel Partners' Rich Wong.

"Mobile app developers need to get discovered, build a marketing channel for mobile users, and scale to massive user bases. With over one billion downloads to date, Getjar has led the industry to create this unique, cross platform app store solution."

GetJar has more than 316,000 developers signed up to its app store, with over 71,000 apps and games available for download.

It plans to expand into paid apps and games before the end of 2010.