Two Cambridge graduates who quit their day jobs to develop a predictive keyboard powered by artificial intelligence are set to become multi-millionaires after their firm was bought by tech giant Microsoft in deal reportedly worth £174 million.
SwiftKey was set up in 2008 by Jon Reynolds and Dr Ben Medlock and their app is now used on 300 million devices every day.
The company has also worked with Cambridge-based Professor Stephen Hawking, helping the scientist and author to upgrade his communications, applying predictive language software to his system and enabling him to speak faster and continue to give lectures.
Mr Reynolds and Dr Medlock said in a statement: "We're excited to announce an important milestone on SwiftKey's journey. As of today, we have agreed to join the Microsoft family."
Microsoft's executive vice president of technology and research, Harry Shum, said of the deal: "We love SwiftKey's technology and we love the team that Jon and Ben have formed.
"That's why today I'm excited to welcome the company's employees to Microsoft. We believe that together we can achieve orders of magnitude greater scale than either of us could have achieved independently."
Dr Medlock studied computer speech and sciences at Cambridge and the pair used his knowledge of natural language patterns and artificial intelligence to create the SwiftKey system, which predicts what a user is typing based on their previous writing habits - finishing words for them so they can write faster.
It started as a side project as both men worked full-time elsewhere following their graduation, with Mr Reynolds in the Civil Service, working on the sale of the High Speed 1 Channel Tunnel rail line.
After founding the company, the pair's first SwiftKey app launched on the Android platform in 2010, supporting seven languages, and quickly took off. It has since been downloaded from the Google Play Store more than 10 million times, and has topped the download rankings in 47 countries.
The app was described as a "revolution" in typing and communication, being named Best Startup Business at the 2012 Guardian Innovation Awards, and coming third in the Sunday Times Hiscox Tech Track 100 - a list of Britain's best private technology companies - in 2014.
Today the app supports more than 100 languages, has been incorporated into many apps as the default keyboard, and is pre-installed on many smartphones as the default typing tool.
Offices have been opened in San Francisco and Seoul, South Korea, alongside the headquarters in Southwark, south London, with the company now employing more than 160 staff.
In 2014 the app was launched on the iPhone, and it was downloaded more than a million times in the US alone in its first time on the iOS App Store.
Since its launch, SwiftKey says its predictive technology has saved users nearly two trillion keystrokes on their devices and more than 23,000 years of combined typing time.
Their statement added: "Microsoft's mission is to empower every person and every organisation on the planet to achieve more. Our mission is to enhance interaction between people and technology. We think these are a perfect match, and we believe joining Microsoft is the right next stage in our journey.
"Eight years ago we started out as two friends with a shared belief that there had to be a better way of typing on smartphones.
"We've come a long way since then; today hundreds of millions of people around the world, and many of the leading mobile manufacturers, rely on our language prediction technology. Our users have saved an estimated 10 trillion keystrokes across 100 different languages, which adds up to over 100,000 years of reclaimed typing time.
"Our number one focus has always been to build the best possible products for our users. This will not change. Our apps will continue to be available on Android and iOS, for free. We are as committed as ever to improving them in new and innovative ways.
"We owe a lot to the invaluable input of our users, including our 130,000-strong VIP community and the many thousands of others who have been with us since the start. Their energy, honest feedback and eagerness to share our products have been the driving force behind our growth.
"At times like this people tend to focus on founders. However, the heart of our company is the awesome team who chose to share this journey with us. We want to take this opportunity to thank them for their dedication and hard work. We never would have come this far without you."