1. Lookout Mobile Security
Mobile device security threats dominated the headlines and the threat landscape in 2011, and Lookout Mobile Security found itself in the perfect position to lock down smartphones and ensure mobile computing is safe and free from security threats. The San Francisco-based startup offers its eponymous flagship application for free for Android, Blackberry and Windows Mobile devices. It protects mobile devices from malware, spyware and unsafe web sites, and also handles backup and recovery of personal data and can locate a mobile device if it's lost or stolen. In December 2010, Lookout scooped up an impressive $19.5 million in Series C funding and Lookout Mobile Security followed that up in September 2011 with a whopping $40 million in venture capital the company said it will use to expand its reach and fortify its threat protection capabilities.