Android (operating system) and rival Linux mobile operating systems that were in development. These established players were skeptical: Nokia was quoted as saying "we don't see this as a threat," and a member of Microsoft's Windows Mobile team stated "I don't understand the impact that they are going to have." Since then Android has grown to become the most widely used smartphone operating system and "one of the fastest mobile experiences available". Reviewers have highlighted the open-source nature of the operating system as one of its defining strengths, allowing companies such as Nokia (Nokia X family), Amazon (Kindle Fire), Barnes & Noble (Nook),
Plug-in electric vehicles in California Annual registrations of plug-in electric vehicles in California increased from 6,964 units in 2011 to 20,093 in 2012, and reached 42,545 units in 2013. In 2014, California's plug-in car market share reached 3.2% of total new car sales in the state, up from 2.5% in 2013, while the national plug-in market share in 2014 was 0.71%. The state's plug-in market share fell to 3.1% in 2015, with the plug-in hybrid segment dropping from 1.6% in 2014 to 1.4%, while the all-electric segment increased to 1.7% from 1.6% in 2014. Still, California's market share was 4.7 times higher than the U.S.