The U.K. is fast becoming a hub for tech startups -- in London alone, the number of tech companies grew 76 percent between 2009 and 2012, to 88,215.
Tech City, a U.K. government-backed initiative to encourage digital companies in an area of east London dubbed "Silicon Roundabout" (pictured), celebrated its third birthday last month. To mark the milestone, Prime Minister David Cameron pledged £15.5 million ($25.5 million) in new funding for innovative firms.
Here, we take a look at the top 10 tech startups in the country, based on The Deloitte Technology Fast 50, which ranked the U.K.'s fastest growing technology companies based on percentage revenue growth between 2008/09 and 2012/13.
— By Anmar Frangoul, Special to CNBC.com