Marissa Mayer, CEO of Yahoo, talked up the company’s mobile growth, although it came with the caveat that in the context of its whole business, “our mobile revenue is still not material”.

In the company’s results conference call, the executive described mobile as a “huge driver of growth”, noting that the company passed 400 million monthly mobile users in Q4 2013. This represents around half of the users seen on the Yahoo network in total.

She also said that its mobile team has grown from under 100 people to around 500 staff over the course of a year.

And addressing the ability to make cash from these users, she observed: “We believe there are some ad products that have the potential to monetise better on mobile than on the desktop. Basically, when you look at ads that are specifically designed for the mobile experience, we believe we can outperform what we have seen in traditional display.”

“We remain confident that there is a big opportunity for Yahoo and we will continue to focus and invest in mobile monetisation in 2014,” she continued.

Mayer has already made a big deal of Yahoo’s mobile progress this year, using a keynote speech at CES 2014 to air the 400 million number.

On a group level, the company reported a net income of $351.7 million, up 28.5 per cent, on revenue of $1.3 billion, down 5.9 per cent.

Its display ad revenue was $553 million for the quarter, a 6 per cent decrease year-on-year, while its search revenue was $464 million, down 4 per cent.