Founder, Summly

Twitter: @nickdaloisio

D'Aloisio is only 18 but already sold his news-summarization app, Summly, to Yahoo for a rumored $30 million, in 2013. The young app developer is now a student at Oxford University, having started undergraduates course in computer science and philosophy in September.

Summly started in 2011 as a simpler version under the name Trimit. It quickly caught the attention of billionaire Li Ka-Shing, who invested $300,000 in the app. After relaunching as Summly, D'Aloisio attracted further investment from Yoko Ono, Ashton Kutcher, and Stephen Fry. Summly was eventually sold to Yahoo, and D'Aloisio worked on the new Yahoo News Digest app. He remains a product manager on the new app, while he studies for his degree.

CEO and cofounder, Dattch

Twitter: @robynexton

Dattch is a dating app for lesbian and bisexual women that connects users based on location. Exton created the app after realising that existing lesbian dating sites were simply reskinned versions of other sites. Using her experience of working with a dating site at a branding agency, she set about making a dating app specifically created for lesbians.

Unlike many dating sites and apps, Dattch has been praised for its positive approach to LGBTQ dating, and the app has won countless awards, including the Best Design award at the 2013 LAUNCH conference. The business brought its operations to the US in 2014, and plans on expanding to Android in the near future.

CEO and founder, Blaze

Twitter: @buzzbrooke

The Blaze laser light is a green laser that attaches to the front of a bicycle. The laser then projects the image of the bike several metres in front of the rider. The bright images keeps cyclists safe on the road by helping drivers to see them.

Over 3,000 laser lights have been sold so far, after devices began shipping in early 2014. Blaze has raised £500,000 from Richard Branson's family and Index Ventures.

CEO, Illicit Encounters

Illicit Encounters is the UK's largest dating site for married men and women, boasting more than 940,000 members in the country, according to the official website.

The controversial company has often seen its ads banned. Illicit Encounters planned a major advertising campaign in 2009, but its proposed ads were rejected and the company is banned from advertising on London taxis. Again in 2010, Illicit Encounters' bus advertising campaign was banned at the last minute, despite having received permission from the owner of the bus company.

European manager, AngelList

Twitter: @pmoe

Philipp Moehring heads up startup network AngelList's presence in Europe, having joined the company in 2014 after working as an associate at the Seedcamp start accelerator.

AngelList works as both a recruitment platform for technology startups as well as a social network for people working in the technology sector.

Cofounders, Toothpick

Twitter: @jozef_wallis

Toothpick is a free app that lets people in the UK book dentist appointments online, sorting by location and availability.

The site claims to have helped over 500,00 people find dentist appointments in the nine months since it launched. It is also endorsed by the National Health Service.

CEO and cofounder, Brainient

Twitter: @emigal

Emi Gal is the CEO of Brainient, a video advertising technology company that is pioneering the use of interactive ads for video. The automatic adverts mean that companies can easily make their own custom-made ads for video, and it's being used by the RAF, National Geographic, and Porsche.

The company grew out of BrainTV, an online TV channel that never got off the ground. Instead, Gal pushed forward with the interactive ad format he developed and launched Brainient in 2009. The company raised a £473,000 seed round in 2009, and a £1.1 million series A investment in 2012.

Founder, Innotech Summit

Twitter: @Jennifer_Arcuri

Jennifer Arcuri is the woman behind one of London's most well-known technology events, the Innotech Summit. The yearly event, started in 2012, helps bring together London's technology scene with the British government.

Thanks to her close ties with London mayor Boris Johnson, the shaggy-haired politician has repeatedly agreed to speak at the event, which also shows the government's interest in the east London tech cluster.

CEO and cofounder, Tapdaq

Twitter: @Nashy

Ted Nash rose to prominence at 18 when he launched his Fit or Fugly app. He was also behind the controversial Little Gossip rumour app for schools, and Rack Stare, an adult-themed game.

Nash's latest venture is Tapdaq, an advertising exchange that lets developers promote their apps inside other apps using the same platform. Tapdaq raised a $1.4 million seed round in September, led by investment from Balderton Capital.

CEO and founder, Picfair

Twitter: @benjilanyado

Benji Lanyado worked as a journalist and developer at The Guardian, Financial Times, and The New York Times, but he left his journalism career behind in 2013 to launch Picfair, a photo service that allows photographers to upload their work and get paid by organisations to use these images for commericals purposes.

Picfair has emerged at a critical time, as an increasing number of artists see their work being used without permission when posted to photo-sharing and social-media sites, like Twitter or Instagram.

Picfair launched with a seed round of $520,000, which included Reddit CEO Alexis Ohanian's first non-US investment.

Founder, Sugru

Twitter: @janeonbike

Sugru is a type of self-setting rubber that was invented in 2003. Stick it onto something, then wait overnight, and you have a ready-made fix that can repair holes, change grips, and work as a kind of superglue. Unlike other products, Sugru can be shaped by hand and sets within minutes.

Dhulchaointigh, from Ireland, used government grants to develop the material. In 2012 the company had over $2 million in annual sales.

CEO and cofounder, Bizzby

Twitter: @Luvaglio

Bizzby replaces the archaic Yellow Pages phone book with an online service that connects the app's 40,000 users to a variety of professional services like cleaners and florists. The company received $10 million in funding in April 2014, just three months after it launched.

CEO Luvaglio is a prolific entrepreneur, having started his first business at 15. He sold his internet business, Just Results, in 1999 for £36 million. Luvaglio was previously known as the man behind the infamous $1 million laptop — which he named after himself.

CEO and founder, Conversocial

Twitter: @joshuamarch

Joshua March founded Conversocial in 2009. It has received $12 million in funding so far. We believe the company has about £6.2 million in annual revenue. The site lets brands use their social-media feeds as customer-relations management tools, making sure that unhappy or angry customers don't turn their unheeded complaints into high-profile social-media fiascos.

Remember the time angry customers hijacked a McDonald's hashtag campaign to complain about the food? Conversocial can help companies deal with that. Its customers include Google, Tesco, and Volkswagen.

CEO and cofounder, Deliveroo

Twitter: @WillShu203

Former investment banker William Shu launched the food-delivery startup Deliveroo in 2013. The company allows customers in the UK to order food from restaurants through the Deliveroo website and app.

Unlike competitor Just Eat, Deliveroo is targeting slightly higher-end restaurants, many of which have not experimented with delivery services before. In September 2014, it was announced that Deliveroo had raised £2.75 million in funding from Index Ventures and Horizon Ventures.

CEO and founder, GoSquared

Twitter: @jamesjgill

James Gill started GoSquared as a project when he was at school with his cofounders. It gradually evolved into a service that monitors web traffic in real time, and the site has become a viable alternative to Google Analytics and Chartbeat.

Now 23, Gill continues to lead the GoSquared team, serving as its CEO since launch. In a recent interview, Gill claimed that GoSquared is used to monitor traffic to over 30,000 sites.

CEO and cofounder, Adzuna

Twitter: @dougall

Adzuna, a search engine for classified listings, lets people discover jobs, cars, and houses online. The company's job- and housing-market data is reportedly used by Prime Minister David Cameron to monitor the UK economy.

Monro launched Adzuna in 2011, having previously worked as COO of property-listing site Zoopla, managing director of online listing site Gumtree, and a senior manager at eBay.

CEO, Appear Here

Twitter: @RossABailey

Appear Here lets small businesses rent commercial space online, making it easy to establish pop-up shops and larger retail outlets. The service has been used by the BBC, Google, Microsoft, and Moleskine to find short-term locations.

CEO Ross Bailey, now 21, founded the company in 2012, and in 2013 it received £1 million in investment from Forward Investment Partners, uSwitch, and Miroma Ventures.

CEO and cofounder, Funding Circle

Twitter: @samirdesai01

Funding Circle is a peer-to-peer lending service that lets users lend money to small and medium-sized businesses in the UK. Started in 2010, £1 million was invested using the site in its first 10 weeks online.

Funding Circle announced in 2013 that it had tripled in size. The site recently claimed that revenue had grown by 177% in the past year and is looking to expand in Europe.

UK Country Lead, Stripe

Twitter: @andyy

Stripe is an online company that helps businesses easily accept payments over the internet. Unlike PayPal, Stripe works as an embeddable online form, with no fees for merchants. Andy Young is Stripe's UK country lead, helping to roll out the payments service here in the UK.

Stripe has ridden a wave of success recently, having announced support for bitcoin and also working as a key part of Apple's new Apple Pay mobile payments system.

CEO and cofounder, Rightmove

Property listing site Rightmove started in 2000 as a joint venture between four of the UK's largest estate agency companies. In 2006 the company was listed on the London stock exchange, and by 2012 the site's revenues exceeded £100 million.

Rightmove's CEO Nick McKittrick helped start the company in 2000, and became CEO in 2013 following his predecessor's retirement.

CEO and founder, Smarkets

Twitter: @jasontrost

Former equities trader Jason Trost founded Smarkets in 2008. The site is a peer-to-peer online betting exchange that lets traders agree odds on everything from sports to politics.

Smarkets charges a base rate of 2% on transactions, 3% cheaper than its competitors. The Sunday Times reports that Smarkets attracted over £200 million in trades in 2013.

CEO, Huddle

Twitter: @alimitchell

Alastair Mitchell founded Huddle in 2006 after UK supermarket giant Tesco acquired the loyalty card startup he previously worked at. Huddle is a file-sharing and collaboration company, and the British government is one of its biggest fans. It has been estimated that the government's use of the software will save UK taxpayers £340 million by 2015.

Huddle is also eyeing a move into US expansion, and it is developing a more secure version of the software for the US government.

CEO and cofounder, OpenGamma

Twitter: @kirkwy

Kirk Wylie is the CEO of OpenGamma, open-source risk-analysis software used by hedge funds and other finance companies. He previously worked in Silicon Valley startups before moving to London and working in the financial services sector. After working in finance, Wylie realised the frustrations that developers have with implementing software, which led him to develop OpenGamma.

General manager, Sprinklr

Twitter: @simonmansell

Mansell is best-known as the founder and CEO of TBG Digital, the company that places Facebook and Twitter ads for companies like Vodafone, Dell, Heineken, and Zynga. TBG was acquired by Sprinklr earlier this year, and Sprinklr is widely expected to be plotting its own IPO, which CEO Ragy Thomas believes will be worth $10 billion.

TBG was founded in a bedroom at Mansell's mother's house in Highgate, London, in 2001. The company still has its London offices in the neighborhood.

CEO, GoCardless

Twitter: @hirokitakeuchi

Oxford mathematics graduate Hiroki Takeuchi founded GoCardless in early 2011 with two university friends. The company is a direct debit provider, allowing small businesses to collect payments online from their customers. Last year GoCardless was reported to serve 3,500 businesses across the UK, with yearly transactions worth $200 million. It raised $7 million in funding from its existing investors at the start of this year.

CEO and cofounder, Skimlinks

Twitter: @AliciaNavarro

Skimlinks started life as a consumer shopping website in Australia in 2006. Founder Alicia Navarro realized after backpacking around Europe that her technology that turned normal web links into affiliate links was the future of the business. Since then, Skimlinks has grown to generate 300 million clicks a month.

In October 2013 it was announced that Skimlinks had been selected as part of a government support scheme that guides companies toward a stock exchange flotation.

CTO and cofounder, Eventbrite

Twitter: @renaudvisage

Renaud Visage is event-finder site Eventbrite's man in Europe, heading up its team of 30 in the UK. When he's not helping roll out the event and ticketing service in cities like Paris and Berlin, Visage works with startup incubators like Seedcamp, Techstars, Startupbootcamp, Le Camping, and TechPeaks.

CEO, Nutmeg

Twitter: @nickhungerford

Former stockbroker Nick Hungerford started Nutmeg while preparing to study for his MBA at Stanford. Hungerford has previously worked as a wealth manager at Barclays and as a director at Brewin Dolphin.

The site automatically builds investment portfolios for investors. Anyone with at least £1,000 can create an automatically managed portfolio on the site. In June 2014 Nutmeg raised £18.9 million from investors including Carphone Warehouse founder Charles Dunstone and ICAP chief executive Michael Spencer.

Cofounder, LiveLeak

Twitter: @HaydenHewitt

Hewitt is the only public staff member of LiveLeak, the controversial video-sharing website that is known as a more uncensored version of YouTube. LiveLeak allows violent content, although there are limits to what can be uploaded. In 2008, Hewitt had to move to protect his family after allowing a controversial anti-Islam documentary to be uploaded to LiveLeak. And in 2014, LiveLeak made headlines when it banned ISIS from uploading beheading videos to the platform to prevent the spread of propaganda.

CEO and cofounder, SuperAwesome

Twitter: @MrDylanCollins

SuperAwesome is a global marketing network that companies can use to promote their products and services to children. It claims to reach over 100 million children a month around the world. In September 2014, SuperAwesome released developer software that allows app developers to introduce child-friendly advertisements to apps without worrying about inappropriate content appearing.

SuperAwesome CEO Dylan Collins is a veteran of the Irish video-game industry, having founded social game company Jolt Online Gaming, which was sold to retailer GameStop in 2009. Previously, Collins founded DemonWare in 2003, which was sold to Activision Blizzard in 2007. The DemonWare technology became the backbone for Call of Duty's multiplayer elements.

CEO and cofounder, Lyst

Twitter: @chrismorton

Lyst is an online fashion marketplace that lets users follow their favorite stores. Chris Morton started the company in 2010 after working as an investor at Balderton Capital and Benchmark Capital. The business is reported to have grown by over 400% in 2012, and again in 2013, generating over $60 million in sales.

In January 2014, Lyst announced that it had raised $14 million in funding from Balderton Capital and Accel Partners, among other investors.

CEO and cofounder, Onefinestay

Twitter: @gregmarsh

Greg Marsh worked on the technology investment team at Index Ventures for three years before founding onefinestay in 2009.

Onefinestay is a high-end Airbnb-style service, letting customers book fancy houses and apartments online for short-term holidays. All customers are given an iPhone for the duration of their stay, and it features a concierge service connecting them with onefinestay's staff for bespoke requests.

In September, Onefinestay launched "folios," collections of high-end properties with themes like "Family," "Work," "Prestige," and "Explorer."

VP EMEA, Facebook

Twitter: @nicolamen

Mendelsohn joined Facebook in July 2013, having previously served as executive chairman of advertising agency Karamarama. She spent 20 years working for advertising agencies before making the move to the social-networking giant. Facebook's London office is one of its largest in the world, and it houses the company's new engineering team.

CEO, Citymapper

Twitter: @azmingo

When Tim Cook announced the Apple Watch recently, Citymapper was one of the handful of apps showcased as part of the presentation. Citymapper founder Yusuf previously worked at Google, as well as in the venture capital and equities fields for international banks. He started the app in 2011 as a guide for Londoners to navigate the city's bus network.

Founder, YPlan

Twitter: @RytisVit

YPlan is an event-finder app that lets people track and find events in their city. The app has become popular in London thanks to heavy advertising on the Underground. In September 2013, YPlan announced that it would be launching in the US by bringing the app to New York.

YPlan founder Rytis Vitkauskas graduated from Harvard Business School with an MBA in 2008. He then interned at Merrill Lynch and other finance companies before joining venture-capital fund Summit Partners.

CEO, Struq

Twitter: @samsbay

Barnett founded advertising tech startup Struq in 2008 with just £2,000. Since then, the ad-retargeting tool has grown to include offices in London, New York, Germany, Brazil, and Turkey. Struq was sold to advertising giant Quantcast in October for an undisclosed sum, making it one of London's most recent tech successes.

CEO, SwiftKey

Twitter: @thejonreynolds

SwiftKey lets you swipe your finger across your phone keyboard to type, as well as learning what words you use by analyzing your emails, Facebook, and Twitter profile. The keyboard has long been a favorite of Android users, and Apple's latest iOS 8 update means that iPhone owners can use SwiftKey too.

SwiftKey's 27-year-old founder Jon Reynolds started the company in 2008 after graduating from Cambridge university with an MA in Natural Sciences. The company raised $17.5 million in funding last year, and now has offices in London, San Francisco and Seoul.

CEO and founder, DueDil

Twitter: @duediler

DueDil makes company and account information easy to find and buy online. The site was launched back in 2011 by serial entrepreneur Damian Kimmelman, who had previously started a design agency and an online gaming platform.

DueDil has gone on to raise $22 million in the last two years. Some of the money raised will be used to bring DueDil's core product to more countries around the world.

Vice president, Silicon Valley Bank

Twitter: @bindik

Bindi Karia joined Silicon Valley Bank in 2012 after working for five years at Microsoft as Venture Capital and Emerging Business Lead. She previously led the BizSpark program in the UK, known today as Microsoft Ventures. Now working at Silicon Valley Bank, Karia is leading the bank's early-stage efforts in the UK and the rest of Europe.

CEO and cofounder, Seedrs

Twitter: @jeffseedrs

Seedrs is a crowdfunding platform for early-stage startups that lets members of the public invest in new businesses for as little as £10. The London-based company started life as CEO Jeff Lynn and COO's MBA project. Lynn is a qualified lawyer, previously working as a corporate lawyer for Sullivan & Cromwell LLP in London and New York.

Seedrs was the first equity crowdfunding platform to receive approval from a financial regulator, a significant win for the company. In September 2014, Seedrs launched the first equity crowdfunding campaign for a publicly traded company when it helped English winemaker Chapel Down raise up to €5 million.

CEO, Just Eat

Twitter: @davidjusteat

Just Eat is an online ordering service that lets people search for local restaurants and order takeaway food. In April, Just Eat was floated on the London stock exchange and valued at £1.47 billion.

CEO David Buttress joined the company in 2013 after working in sales for Coca-Cola for eight years, where he won the account manager of the year award.

Founder, Mind Candy

Twitter: @acton

Michael Acton Smith is one of the most well-known figures in the London startup scene. After launching online retailer Firebox in 1998, Acton Smith went on to create Mind Candy in 2004. The game company's main product, Moshi Monsters, had grown to 90 million users by 2013.

Acton Smith is also responsible for helping to bring east London's startups together. He started the regular Silicon Drinkabout meeting sessions as well as Ping Pong Fight Club, another social occasion for startup employees and founders.

In July, Acton Smith stepped down from his role at Mind Candy to pursue a more creative role in the company, but remains a key figure in London's technology scene.

CEO and founder, Moo

Twitter: @richardmoross

Moo's office is right in the centre of east London's tech cluster, which might seem like a strange place for a printing company famed for its high-quality business cards to be located. But Moo has built up a reputation for innovation. It has launched near field communication-enabled cards that let people use their smartphone to visit a company website. In 2012, Moo acquired online portfolio site flavors.me.

Moross founded Moo in 2004, previously working as an advertising executive at sorted.com and as a senior strategist at Imagination, the world's largest independent design agency. He's famed for the annual Moo parties, held at its compound in east London and attended by many London tech figures, including startup founders and television presenters.

VC, Passion Capital

Twitter: @eileentso

Eileen Burbidge founded investment fund Passion Capital in 2011 with Stefan Glaenzer and Robert Dighero. Since then, Passion Capital has invested in a series of successful London companies including DueDil, GoCardless, GoSquared, and Smarkets.

Prior to founding Passion Capital, Burbidge worked at Apple, Yahoo, Skype, and Sun Microsystems.

Founder, Wikipedia

Twitter: @jimmy_wales

Jimmy Wales is the public face of Wikipedia and a regular figure in the London technology scene. After starting the online encyclopedia in 2001, Wales has been running additional projects including the Wikimedia foundation and the Wikia web-hosting service.

Wales was extremely critical of the European Court ruling in May 2014 that meant people could force Google to hide information about themselves from Google search results.

General partners, Google Ventures Europe

Twitter: @ediggs

Eze Vidra is best known in London as the head of Google Campus, Google's large coworking office space for startups in the middle of the east London tech scene. He's also behind the Tech Bikers charity effort, started in 2012, where startup founders and employees participate in a long-distance bike race from Paris to London to raise money for charity.

Now Vidra is a general partner at Google Ventures Europe, the company's startup investment fund.

Founders, TransferWise

Twitter: @kaarmann and @taavet

Money-transfer service TransferWise has seen rapid growth in Europe since its launch in 2011. Earlier this year the company claimed to have processed £1 billion in customer money.

Hinrikus previously worked as Skype's first employee, while Käärmann was a manager at Deloitte. They founded TransfewWise in 2011, and it has become the go-to site for transferring money in Europe.

CEO and cofounder, King

Twitter: @RiccardoZacconi

Zacconi founding European gaming giant King in 2003. The company nearly folded that same year before a last-minute investment on Christmas Eve. Since then, it's raised millions in venture capital.

The London-based company's successful freemium games Candy Crush and Bubble Witch Saga led King to IPO in March 2014, which saw it valued at $7.08 billion.

CEO and cofounder, Zoopla

Twitter: @AlexChesterman

Zoopla was founded in 2007 by serial entrepreneur Alex Chesterman, one of the cofounders of movie-streaming service LoveFilm, which was sold to Amazon in 2011. As well as serving as CEO of Zoopla, Chesterman is an active investor; he has investments in sports e-commerce site SportsPursuit and student booking site Uniplaces.

The website, which covers the British residential property market, rose to prominence by acquiring almost all of its competitors. In five years, it bought 11 competitors, leaving Rightmove as the only rival. In June 2014, Zoopla had its IPO, and the company was valued at £919 million.

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