2010 is a booming year for Lookout Mobile Security, a leader in cloud-based smartphone security, as it reached over 4 million registered users in less than a year’s time. In order to improve mobile security offerings and accommodate millions of users, the company raises an additional $19.5 million in a series C round of funding led by Index Ventures, in participation of Accel Partners and Khosla Ventures. Also, Index Partner and former Cisco Executive, Mike Volpi, joins Lookout’s board of directors.

“Smartphones are the next computer for billions of consumers and it’s clear that, just as in the PC world, consumers and their phones need protection,” said Mike Volpi, Partner, Index Ventures. “Lookout’s unique blend of a qualified executive team, demonstrated success with consumer adoption, and careful balance of ease-of-use and sophisticated security technology, positions the company for success and rapid growth in 2011.”

A survey conducted by Gartner Research reveals that the global smartphone sales increased by 96% from third quarter last year, and subsequently explodes the application market to hundreds of thousands of apps. However, as users do more with smartphones because of its added sophistication and power, mobile hardware attacks are getting a lot more common over the past few months. A recent one is a Trojan concealing itself as a “movie player” application for Android.

This app sends premium rate SMS messages and unknowingly charges money to users’ phone bills. Lookout is a comprehensive protection for mobile phones from such malicious attacks. You’ll never have to worry about trying as many apps as possible. Moreover, using an ordinary browser, you can locate your mobile phone in case you lost of misplace it, access your back up files on the cloud in case of permanent damage or theft.

“2010 was a year of tremendous growth for Lookout. We skyrocketed to four million users, launched a successful premium service and gained industry and consumer accolades,” said John Hering, CEO and founder, Lookout Mobile Security. “Moving into 2011 mobile security will be critical. The solution needs to be complete and address the growing needs of smartphone users for protection. This investment will help Lookout expand to other platforms and develop additional security services to protect consumers.”

Lookout currently has more than 400 mobile networks in 170 countries, offering free and premium services. Moreover, it was recently selected as top technology product of 2010 by PC World.

Lookout Security launched a premium service on top of its existing free one this year, which moved it from the asset status to a money-making venture. The personal and mobile are both expected to grow out of their current proportions next year – at least according to IDC – meaning that mobile security is heading towards PC security industry scales.

In our previous coverage of Lookout Mobile Security, we covered the company’s mobile security tips release. These included setting a password, a recommendation to download platform updates, mobile apps downloading ‘discretion’ and more.