It's the classic Silicon Valley success story of a young software prodigy striking it ridiculously and improbably big. But this time the spotlight is shining on the other side of the pond.
D'Aloisio, who taught himself to write software at age 12, built the free iPhone app Summly - which automatically summarizes news stories for small screens - in his London bedroom in 2011. He was just 15 years old.
Soon he had backing from Horizons Ventures, the venture capital arm of Hong Kong billionaire Li Ka-shing and big names such as Zynga Inc.'s Mark Pincus and actor Ashton Kutcher.
Before it was pulled from the app store Monday after the announcement of the Yahoo deal, D'Aloisio's app Summly had been downloaded nearly 1 million times. It had deals with 250 online publishers, including News Corp., and 10 employees in London. Not bad for a high school student.
"To me, Yahoo is the best company to be joining right now because it's one of these classic Internet companies," D'Aloisio said in an interview. "With new leadership from Marissa Mayer, Yahoo has a strong focus on mobile and product, and that's the perfect fit for Summly."
Mayer, the former Google Inc. executive who took over the Sunnyvale, Calif., company last summer, has focused on mobile technology to revive Yahoo's lagging fortunes. She has snapped up a number of promising mobile startups as much for their personnel as for the innovation.
In D'Aloisio, Yahoo is getting someone who truly thinks and lives in the mobile world.
Rather than browsing the Web by clicking a mouse, more people are connecting to the Internet with their smartphone or tablet, changing what kind and how much information they consume, Yahoo mobile chief Adam Cahan said. Silicon Valley companies such as Facebook and Yahoo are looking to adapt their Internet businesses to hold on to consumers who want easier, faster ways to find what matters to them.
"Summly solves this by delivering snapshots of stories, giving you a simple and elegant way to find the news you want, faster than ever before," Cahan said.
D'Aloisio, who took a break from school for six months to focus full time on Summly, will join Yahoo's London office while continuing his studies in the evenings and living at home with his parents. He says Yahoo plans to integrate Summly into all sorts of mobile experiences.
"The real idea is to take the core of the technology and find different fits for it and make it as ubiquitous as possible on the Web," he said. "We want to take summarization and build beautiful content experiences around it."
He says his parents - his dad is an energy financier, his mother is a lawyer - will help him manage the financial windfall (he says all he wants is a new computer and pair of Nike trainers). But he says he was not driven to the deal by dollar signs.
"Technology has really been the driver behind this whole deal," D'Aloisio said. "I can't wait to see how it plays out at Yahoo."
D'Aloisio is just one of a number of under-21 entrepreneurs who have made millions at a very young age.
Patrick Collison, who took his first computer class at age 8 and entered young scientist competitions as a teen in Ireland, was just 19 when he and his brother John sold their Silicon Valley startup Auctomatic to Canadian company Live Current Media Inc., a deal that made them overnight millionaires.
"It was helpful perspective to have something like that happen very early on," said Collison, who is now co-founder and chief executive of San Francisco payments startup Stripe. "It shows you that it's not all that big a deal. Yes, it's wonderful to create something that someone is interested in acquiring, and it's nice to have more money than you had before, but really nothing changes. Enjoying what you do on a day-to-day basis is what's important."
The sudden flash of worldwide media attention has been a bit overwhelming, D'Aloisio said. But not in a bad way.
"It's been an absolutely awesome experience," D'Aloisio said. "I'd love to do it again someday with another company."
Spoken like a true entrepreneur.