Taboola is best known for serving content recommendations on the websites of notable publishers, including USA Today, The Huffington Post, and Time magazine. Now the New York City-based startup is expanding its global footprint by teaming up with Yahoo Japan to offer personalized recommendations to millions of users. Taboola already works with premium online publishers in Europe and has a presence in India thanks to its work with NDTV, a 24-hour Hindi news channel. 

The new partnership, announced Wednesday morning, will roll out in Japan in September, with a particular focus on ramping up audience engagement on Yahoo News. To prepare for the launch, project managers at Yahoo News will work closely with Taboola's engineers to build a scalable recommendation business that drives more traffic on Yahoo News and its partners' sites. 

"I think it's another step forward in validating this native advertising and content discovery space," Taboola founder Adam Singolda told Inc. in an interview Tuesday. "Every 10 years there's a market transition driven by the behavioral change of users." This time around, he says, the change is the widespread adoption of smartphones, a development he thinks Taboola can capitalize on. 

Although smartphone penetration has been slower in Japan than in some other industrialized countries, research firm eMarketer predicts that 60.2 percent of the population will own a smartphone this year, more than double the figure in 2012. According to Singolda, smartphones account for more than 30 percent of Taboola's business, up from 22 percent last year. It's a lucrative opportunity for the seven-year-old startup, which has raised $40 million in funding to date. 

Six months ago, Taboola "was looking for strategies to go global outside the U.S. and a place where our technology can get a lot of scale," Singolda said. By a stroke of luck, Yahoo Japan reached out over email and the two companies began spending time "getting to know one another." The courtship was a lengthy one, but in the end both companies believed there was a fit.

Yahoo Japan drives 8.5 billion pageviews per month. Taboola already serves 130 billion recommendations per month to 350 million people, so scaling should be easy enough, says Forrester analyst James McQuivey--that is, he adds, if the market isn't already saturated with Taboola competitors.