Yahoo Now Has 400 Million Monthly Mobile Users, Marissa Mayer Says

When Marissa Mayer took on the CEO job at Yahoo, she knew it needed to up its game in mobile.

She told the board: "I think the mobile wave, if we can catch and harness even part of it, can really propel us." So she said on stage to Salesforce.com CEO Marc Benioff during the Dreamforce conference Tuesday night.

But four days into the job she got a unpleasant surprise.

She was hanging out at the Yahoo cafeteria when an employee named Tony introduced himself as a mobile engineer.

"Great!" she told him, "How big is the mobile team?"

"30 people," he told her.

She clearly looked shocked, so he added, "Oh, but there's more in the [product] teams. Maybe 60."

Yahoo employed about 15,000 people at the time. (It currently employs about 12,500.)

So she went straight to engineering and asked them how many mobile engineers they had. They told her "like 100" and she asked "like an actual 100? Or 60 rounded up to 100 to make me feel better?"

Answer: 60, to which she replied, "We're going to have change that really fast."

She promoted Adam Cahan to become the new head of mobile engineering and started hiring and acqu-hiring.

Today there are about 400 mobile engineers, she says.

Yahoo now also reaches 400 monthly users on mobile.

That's up from the numbers she discussed just few weeks ago, on stage at the TechCrunch Disrupt conference in September. At that time she said Yahoo had 350 million mobile users. Plus, ComScore's new report says that Yahoo reaches 82% of U.S. mobile users.

That sounds like good news even if it hasn't materialized in fantastic new growth in revenues yet.