25. Robyn Exton
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.
24. Judith Clegg
Founder, Takeout and Glasshouse
Twitter: @judithclegg
Judith Clegg is the founder of two companies that work closely with the UK's tech industry.
Takeout is a consultancy that connects startups and larger businesses such as Microsoft with academics and new business opportunities. Her other company, Glasshouse, is an events business favoured by big-name tech companies like Craigslist, Index Ventures, Moo and Mind Candy.
23. Emily Brooke
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.
22. Natalie Downe
Cofounder, Lanyrd
Twitter: @Natbat
Lanyrd lets you discover new conferences and professional events, and see which conferences your friends will be attending. Launched in 2010, it was one of the first Y Combinator companies, raising over $1.4 million in funding.
Downe has been Lanyrd's chief product officer since the company's inception, working to design and engineer the site. She also works as Eventbrite's director of organizer acquisition, helping bringing new conferences and events to the platform.
21. Jennifer Arcuri
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.
20. Jane Ní Dhulchaointigh
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.
19. Julia Fowler
Cofounder, EDITD
Twitter: @jul_ia
EDITD is bringing big data to the fashion industry, helping clothing designers understand exactly what it is that customers want. It works with brands such as Gap, ASOS and Target to help them understand the data of fashion using real-time analytics.
Fowler founded EDITD in 2010 with experienced IT professional Geoff Watts.
18. Michelle You
Cofounder, Songkick
Twitter: @wreckingball37
Songkick was one of the London startup scene's first big success stories. The site lets people track their favourite bands to see when and where they will play.
You founded Songkick in 2007, and has served as its Chief Product Officer ever since. Before starting the company, she was the managing editor of Theme Magazine and an associate at Random House.
16. Bindi Karia
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.
15. Elizabeth Varley
Founder and CEO, TechHub
Twitter: @evarley
Elizabeth Varley founded TechHub in 2010 after realising that London was lacking in shared workspaces for tech companies. TechHub was one of the first hubs for tech startups in London, situating itself around the Old Street area. In 2012 it opened up office space in Google Campus, a larger workspace for internet startups sponsored by Google.
The company is jointly run with TechCrunch's Editor-At-Large Mike Butcher, and TechHub has expanded to locations including Bangalore, Bucharest and Riga.
14. Kathryn Parsons
Founder, Decoded
Twitter: @KathrynParsons
Kathryn Parsons founded Decoded in 2011 with the aim of teaching people how to code in just one day. Courses at her computing workshop start at £750, and teach people the basics of how to write programs. Her clients include employees from companies such as the BBC and Facebook. Parsons is in a relationship with another of London's well-known tech figures: Michael Acton Smith, the founder of Mind Candy.
13. Colette Ballou
President, Ballou PR
Twitter: @coletteballou
Colette Ballou started Ballou PR in 2002, just as the European startup industry began to emerge. Since then, she has worked with some of the word's fastest-growing technology companies, including Autonomy, Evernote, Facebook, Flipboard, Groupon and Zendesk.
In 2011 she sold the US wing of her company to MWW Group, moving to focus on Europe only. She's a regular figure at startup events, offering sage advice on how to grow companies.
12. Natalie Massenet
Founder, Net-a-Porter
Twitter: @NatalieMassenet
Natalie Massenet founded online fashion portal Net-a-Porter in 2000 when she was trying to find designer goods for a fashion shoot. Net-a-Porter sells clothes using a layout similar to traditional fashion magazines. Before starting the site, she worked as a fashion model in Tokyo, assistant at Tatler, fashion stylist, and also worked with photographer Mario Testino.
Massenet has gone on to become Chairman of the British Fashion Council, and she received an MBE in 2009 for services to the fashion industry.
11. Reshma Sohoni
Cofounder and Partner, Seedcamp
Twitter: @rsohoni
Reshma Sohoni is one of the cofounders of Seedcamp, a London-based investment fund and mentorship program for tech startups. She started the company in 2007 with Saul Klein, and the fund has gone on to invest in over 30 companies, including Frontback, Socialbro, TransferWise, Brainient and EDITD.
Before starting Seedcamp, Sohoni worked in M&A in the US and India during the dotcom boom, as well as holding management positions at Vodafone.
10. Eileen Burbidge
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.
9. Sonali De Rycker
Partner, Accel Partners
Twitter: @sonalidr
Accel Partners is one of London's most respected venture capital firms, with a strong stable of tech talent. And De Rycker is one of Europe's most experienced capitalists, having worked for over 14 years investing in startups.
De Rycker has overseen investments in big-name European startup successes such as Spotify, Moo, Seatwave and Wonga. She's also an independent director on the board of IAC.
Starting her career as an Analyst at Goldman, Sachs & Co., she went on to join Atlas Venture in 2000.
8. Roxanne Varza
Startup Lead, Microsoft France
Twitter: @roxannevarza
Roxanne Varza heads up Microsoft's startup relations team in France, including the Bizspark program and Microsoft Ventures. But she also makes an impact here in the UK, helping British startups and also working as cofounder of European technology news site tech.eu.
Born in San Francisco, Varza moved to France, where she started the TechBaguette blog to report on French technology companies. Varza also worked for TechCrunch before founding the Paris and London chapters of Girls In Tech and joining Microsoft in 2012.
7. Avid Larizadeh
General Partner, Google Ventures
Twitter: @avidl
Avid Larizadeh is the only female member of Google Ventures' recent expansion into Europe. Before joining the VC fund, she was the cofounder of fashion retail Boticca.
Larizadeh also held product management roles at Skype and eBay in addition to being an Entrepreneur-in-Residence at Accel Partners.
6. Joanna Shields
Advisor to the Prime Minister on the Digital Economy
Twitter: @joannashields
Joanna Shields has been one of the London technology industry's most well-known success stories. She started working in tech in 1989 as a product manager for Efi in Silicon Valley.
In 1997 Shields became the CEO of video streaming company Veon, which was acquired by Philips in 2000. After that, she became Google's Managing Director for Europe, Middle East and Africa.
Shields became the President of Bebo in 2006, where she oversaw the company's sale to AOL for $850 million. In 2009, she was recruited by Sheryl Sandberg to run Facebook in Europe. And in 2012, Shields entered government when David Cameron asked her to run the UK Tech City investment scheme. Shields was appointed an OBE in 2014 and named a working peer in August.
5. Martha Lane Fox
Cofounder, Lastminute.com
Twitter: @Marthalanefox
Lane Fox launched online travel site Lastminute.com in 1998 during the dotcom bubble. It was one of the few businesses to survive the crash, going on to be purchased for £577 million in 2005. Since stepping down from Lastminute.com, Lane Fox has served on boards of companies including Marks & Spencer and Channel 4.
Lane Fox is also known for her work within government. She has worked tirelessly to modernize the government and to encourage the public to become more computer literate. Lane Fox entered the House of Lords in 2013, becoming its youngest female member.
4. Alicia Navarro
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.
3. Nicola Mendelsohn
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.
2. Jo Bertram
Regional General Manager - UK, Ireland & Nordics, Uber
Twitter: @jo_bertram
Jo Bertram joined Uber in 2013 after working as a management consultant for McKinsey and Accenture. Now, she manages the on-demand ride service's operation in the UK, Ireland and Nordics. Those are important markets for the app, which has seen frequent protests from London's iconic black cabs and even its own drivers.
Bertram has guided the company through those tricky periods, even managing to turn those protests to Uber's advantage after sign-ups increased 850% following a protest in London.
1. Sherry Coutu
Angel investor
Twitter:@scoutu
Sherry Coutu is regarded as one of the most influential people in London's technology industry. She has over 20 years experience as an entrepreneur, having founded two financial services companies.
Coutu's list of personal investments is an impressive selection of some of the UK's most exciting companies: PeerIndex, Brainient, YPlan, DueDil are amongst some of the names.
She is also an advisor and board member to companies such as LinkedIn, Zoopla, London Stock Exchange, BBC Worldwide Labs, Seedcamp and Cambridge University Press.