Twitter has made another acquisition to build the social network’s ad tech business — specifically in the area of native ads. It has acquired Namo Media, a specialist in “native ad” content that integrates with the site where the ads are being viewed, with a focus on mobile ads. Twitter is not commenting on the price, but I have heard from reliable sources that it is around $50 million.

Namo Media is closing down its standalone operation and integrating into the Twitter-owned MoPub platform, the startup wrote in a blog post announcing the news. There are around eight people working for the startup now and from what I understand most will be joining Twitter.

The idea of seamless ads fits in with how Twitter has been trying to ramp up its own advertising business both on desktop and mobile versions — eschewing banners and ads in the margins in favour of tweets, and more recently cards, that appear in a user’s Twitter stream in the form of Promoted Tweets and Promoted Accounts.

“Since we acquired MoPub last October, we have been working to bring native ads to mobile app publishers in order to create a more seamless and less intrusive ad experience for users,” Twitter’s ad head Kevin Weil wrote in a blog post announcing the deal. “We believe strongly that all app developers large and small should be able to monetize their applications without sacrificing the user experience.”

The cards that Twitter has been integrating into its stream have been growing in terms of the kinds of features that they cover — from buttons to get people to request more information, to videos and so on (with commerce potentially coming soon too?). So what Namo will bring is technology and engineers/expertise to expand that set of features. One recent example included adding a carousel-style feature to Namo’s ad format.

Given that Namo has built a business that works on native ads for various mobile publishers, this is a further sign of how Twitter has ambitions to play beyond its own walled garden. That concept, incidentally, is something that Namo’s CEO Gabor Cselle has said in the past was an area that interested him.

Namo Media has put all of its effort into mobile ads — which makes sense, since on a mobile screen there is a constraint for space, and therefore even more of a need to be more creative with how you present information to users. It’s also a business that has so far seen not brilliant margins, so adding better and richer experiences (like carousels) could lead to rises in CPMs for these ads.

This matches up well with how Twitter has been growing: the company, in its last earnings report, said that it now has 198 million mobile users, working out to 78% of its users accessing the site from a mobile device. On top of that, more than 75% of its ad revenues are coming from mobile.

In other words, it makes a lot of sense for Twitter to be pressing on with how to improve that business and its margins in it even more. Both Twitter and Namo have been skating to where the puck is going to be, so to speak.

There are also some other interesting twists here that are also worth mentioning. Co-founder Nassar Stoertz, who leads Namo’s engineering efforts, had worked previously at Google, with his last role there focusing on its Wallet services, and previous work including time spent working on Gmail. Co-founder Tural Badirkhanli is also an ex-Googler who had spent time specifically in Admob. He has also worked on an email startup. Cselle also had spent time at Google where he worked on — yes — Gmail (after it acquired a previous startup of his, reMail) and Google Now. He’d also in the past been VP of engineering at Xobni (now part of Yahoo).

What I’m implying here is that while there is some clear talent and technology in ads, Twitter is getting a team of seasoned engineers. Right now they will be tasked with mobile ads, but who knows what else they may do longer term?

San Francisco-based Namo Media was backed by a number of top investors such as Google Ventures, Andreessen Horowitz, Betaworks, Trinity Ventures, Susa Ventures, Chung-Man Tam, Kevin Scott, Garrick Toubassi, Ben Ling, Michael Levit, Tikhon Bernstam, and Paul Buchheit, and had raised just under $2 million, according to Crunchbase.

Updated after publishing with price and more details.