Yahoo has made no secret of its ambitions and advances in mobile, earlier this month reporting 450 million monthly active users and search and display mobile ad revenues growing 100%. In CEO Marissa Mayer’s words, Yahoo is a “mobile first company.”

Now, sources say that Yahoo has closed in on an acquisition that could potentially boost its role in mobile further: it is buying Flurry, the mobile app analytics and advertising startup, with a price that could be anywhere between $300 million and $1 billion. Kara Swisher is also reporting that Yahoo is interested in the company.

Update: A source is telling us that the price was substantially lower, clocking at around $200-$300M. And Yahoo has confirmed the acquisition.

As one poster on a Secret note about the rumor described it, “The price will be low if it’s value[d] as an ad tech company, high if it’s valued based on the analytics SDK footprint. Marisa [sic] likes to overpay for things.”

We have reached out both to Flurry and Yahoo for comment.

We’d been hearing for a while now that Flurry was on the market, with one source suggesting it was looking for a price of around $700 million – $800 million. Other potential buyers, we heard, included Amazon. But given how far Amazon itself has advanced in building its own mobile analytics services to court more developers, it looks like that ship sailed on its own.

The Secret note posted about a Flurry sale to Yahoo is now deleted, it seems, but this is how it looked:

One source close to Flurry says the company has been “racing toward a sale” and confirmed that Yahoo was looking like the most likely buyer for a while now, with a sale made public by the end of the summer.

“Yahoo was a pretty open secret around the office,” the source said. “Their team came by for executive meetings several times over the course of several months.”

Founded in 2005 and headquartered in San Francisco, Flurry is one of the largest companies in the area of app analytics.

It’s an area that has seen some consolidation. For example, Onavo was acquired by Facebook. AppAnnie has acquired Distimo. And Twitter has also made a number of acquisitions that have boosted its mobile analytics capabilities.

In Flurry’s own words, “Since the launch of the smartphone, Flurry has helped grow the app economy into a $100+ billion industry.” By that, it’s referring to the fact that it works with some 170,000 developers, picking up data from 150 billion app sessions each month, to provide information to app publishers about their audiences, app usage and app performance, providing insights to improve how apps work.

And to improve how apps make money. Flurry uses that data, for example, to power its advertising platform, which is used by brands to target specific audiences on apps in Flurry’s network, and by developers to monetise their apps with more relevant inventory.

It has raised close to $74 million, with backers including Borealis Ventures, Crosslink Capital, DFJ, Draper Richards, First Round, InterWest Parnters, Menlo Ventures and Union Square Ventures.

Of course, Yahoo seems to be a strong candidate for lots of wild mobile acquisition rumors. But you can see where Flurry fits well with Yahoo’s existing business focus, specifically across mobile, advertising and B2B products. Especially as the company continues to see pressure on its more legacy businesses like desktop display advertising revenue and search revenue.

Specifically, what Flurry could give to Yahoo is not just a boost in mobile advertising revenues, but, as Yahoo builds out its ad tech business, a more central role in how others are monetising and using mobile.

Effectively, this gives Yahoo another strong string to its mobile bow: while it builds out its own apps and app inventory, and advertising to run across them, Yahoo could be bringing in a platform that could become the go-to place for other mobile players to boost and develop their own app businesses.

“Flurry draws in more behavioral data from mobile apps than any other company, and we put it to work to help app marketers build a high quality audience,” Flurry notes on its site. “Flurry serves video, banners and interstitial ads using the most advanced targeting technology in mobile today to increase installs, campaign ROI and retention. Cross promoting your own apps is always free with Flurry.”

Yahoo says that the 450 million monthly active mobile users it recorded in Q2 was over 100% growth over two years (in 2012 the figure was 200 million). Mayer, in her earnings report remarks, also noted that the time spent by its audience on mobile was up by 79% in the last year. She said that the company has “more than 400 Yahoos working exclusively on building iOS and Android apps.”

She also mentioned mobile search as a place for further concentration — an area where Flurry’s mobile app analytics could also come in usefully. “We really believe that the mobile search experience to be completely different than that of traditional desktop search,” she said. “There is a clear opportunity here and we are continuing to look at ways to deliver more innovative, more intuitive search experiences on mobile phones.”

In the search for new growth and business lines that could potentially give the company a stronger counterbalance against Google, Yahoo has been building up its mobile business, both in terms of products and talent to develop and run them.

A lot of this has come by way of acquisitions. Since Marissa Mayer took over as CEO in 2012, there have been 30 known acquisitions either directly or indirectly related to mobile products (we’re listing them below for those interested in keeping track).

That’s not counting IntoNow, a social TV app Yahoo acquired in 2011 before Mayer joined the company. IntoNow’s co-founder and CEO Adam Cahan is now the SVP overseeing all mobile and emerging products at Yahoo.

Recent mobile acquisitions, most recent first:

Blink Wander Incredible Labs Tomfoolery Cloud Party (not mobile but cloud-based) SPARQ Aviate PeerCDN (not for mobile specifically but improves all website speed which is helpful to mobile) Quik.io Ptch SkyPhrase – natural language processing to make data such as web analytics and sports (‘Siri 2.0’) LookFlow Bread Hitpost IQ Engines Admovate Qwiki Bignoggins Productions GhostBird Software PlayerScale Tumblr (social network but with mobile apps) Loki Studios MileWise GoPollGo Astrid Summly Jybe Propeld Snip.it Stamped

(H/T Ryan Sarver)

Article updated to reflect pricing information and that the acquisition has been confirmed.