With Marissa Mayer at the helm, Yahoo is on an acquisition tear. 

One month after the company's $1.1 billion acquisition of Tumblr, AllThingsD reported yesterday that Yahoo is in talks to purchase Xobni, an address book app, for $30 million to $40 million. And today, news surfaced that the company is also about to acquire Qwiki, a popular video sharing app, for close to $50 million. If the two deals go through, Yahoo will have publicly acquired 14 companies in 2013; by comparison, last year it bought only two companies, and, in 2011, three. 

No Surprise, But What's the Strategy?

When Marissa Mayer took over as Yahoo's CEO in late 2012, one of her first stated missions was to sniff out potential acquisitions in order to turn Yahoo back into a growth company. And with $1.2 billion in cash on hand--even after the Tumblr acquisition--she has room for several more big purchases before 2014.

"We're looking for smaller-scale acquisitions that align well overall with our businesses," Mayer said on a shareholder conference call in October 2012. Ken Goldman, the company's CFO, chimed in saying, "Our primary objective as a new management team is to leverage our assets, competitive strengths, and available resources to transition this company from financial stability to a growth business."

What's puzzling to me, though, is the strategy behind these acquisitions on a whole. 

In just six months, Mayer the 14 deals have been spread over a wide variety of areas. You have to wonder if Yahoo is just shooting from the hip at this point, hoping that at least one brings in new revenue. Even though Yahoo is beating Wall Street profit estimates, its core advertising business is suffering, and it's clear that Mayer is looking for some way to make money.

That said, two loose themes emerge from Mayer's deal-making moves, but I'm skeptical about both.

Building Out Mobile

Yahoo has an impressive 300 million mobile users, but that's about half Facebook's mobile user base. Mayer has been vocal about aggressively trying to capture a larger mobile audience. Last month, at the Wired Business Conference, Mayer said that the biggest goal right now is to have "Yahoo persistent on every smartphone, tablet, and PC for every Internet user."

Of the acquisitions Yahoo has made so far this year, several were focused on expanding mobile capabilities, including Summly, a news app; Loki Studios, a gaming start-up; aLike, a recommendation app; and Ghostbird software, a photo app.

Anecdotally, it seems Mayer is ready to attract the best mobile talent, too. Reports The Post:

"Employees chosen to work on the all-important mobile mission are given the coolest and latest laptops, the best, most recently redecorated offices and prompt access to Mayer's office, according to interviews with several Yahoo insiders."

But mobile expansion will be tough for Yahoo, even with a slew of upstarts and new thinkers in the space. Unlike its competitors like Facebook and Google, Yahoo never made the leap into hardware--which will make Mayer's hope to be on every device all the more difficult. 

Making Yahoo More Social 

Clearly Mayer's other big bet is to revitalize Yahoo by making it more social. Some were skeptical about Mayer's $1.1 billion acquisition of Tumblr--which only had about $13 million of revenue in 2012--but it's apparent Mayer sees the company as a vehicle to tap into one of the most active social platforms on the Web, along with a somewhat different advertising model. 

As Adam Rifkin writes

"In some ways, Tumblr is actually Facebook 2.0! As Facebook has become a real-life social network infested with parents, co-workers, ex-friends, and people you barely know, Tumblr has become the place where young people express themselves and their actual interests with their actual friends."

But Yahoo's foray into social will be fraught with challenges. Tumblr's core demographic is the 18-to-24-year-old bracket, a notoriously fickle cohort. Yahoo's other "social" purchases--like its January 2013 acquisition of Snip.it, which lets users collect articles--don't have much to do with Tumblr.

It's too early to see if Mayer's acquisition strategy will pay off, and Mayer knows it'll take time to see if the deals deliver material results to the core business. As she said on an April 2013 shareholder call:

"Overall, I have been very pleased with how well our talent acquisitions have integrated into the company. You'll see many of the contributions come to life in our product experiences over the next few months. So stay tuned."