Another big name on the European tech scene is online photo printing service PhotoBox, which was founded 15 years ago and now has 7 million active customers across 20 countries. It acquired online greetings card company Moonpig.com over three years ago and secured a £50 million revolving credit facility from banks earlier this year to fund more mergers and acquisitions.
CEO Stan Laurent told CNBC that the company's focus was currently on growth, rather than becoming an acquisition target or floating on the stock market.
"The main areas that we're interested in are product innovation around personalization, mobile expansion and geographical expansion," he said, but added that PhotoBox wasn't looking State-side any time soon.
"We've decided not to expand into the U.S. for now. We still have only around 8-9 percent of Europe's total photo-printing market share, so our focus is very much European countries right now," he added.
Burbidge said the Photobox team had built a solid company over the years, and had proved its ability to grow both organically and through successful acquisitions.
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"They've shown that they're willing to work with new teams and build new features. For nearly 15 years they've reacted and responded to what the market wanted," she told CNBC. "And the online personalised-gift market is only going to get bigger. People aren't going to tire of this; they want quicker, faster more novel gift ideas."
It might be newer and smaller than the companies above, but money transfer platform TransferWise has caught the attention of some big-name investors. In June it raised $25 million in funding from Richard Branson and Paypal co-founder Peter Thiel.
Another company Money transfer platform TransferWise has caught the attention of some big-name investors, raising $25 million in funding from Richard Branson and Paypal co-founder Peter Thiel in June.
It was co-founded by Taavet Hinrikus, Skype's first employee, in 2010. He was frustrated by the costs involved in transferring money abroad, and devised a peer-to-peer transfer system using the mid-market exchange rate.
The company has big expansion plans – it currently supports 20 currencies, and is on track to launch another 10 currencies in the fourth quarter of this year.
Passion Capital's Burbidge said Transferwise was "well on its way" to being a major European player on the tech scene.
"It's a relatively new company and has an attitude that is really disruptive, which people love," she added.