It has been a long time coming, but Google search requests made on mobile devices recently overtook those made on PCs in the U.S. in sheer number.

This is the first time that this has ever happened, and it highlights the shift in attention to mobile use rather than desktop use. Because of this shift, Google has announced a number of new mobile advertising tools.

"We've hit an inflection point," said Google VP Jerry Dischler, head of product management for search ads. "There are now more Google searches on mobile than on desktop in 10 countries, including the U.S. and Japan. We've anticipated this moment, seen this trend coming for several years now, and have been investing ahead of the opportunity."

Along with the announcement that mobile has overtaken desktop in search came the announcement of a number of new mobile advertising tools and formats for advertisers. These new formats are designed to stand out at the top of the page, cutting down on the amount that users have to scroll down the page. Ads pull information from things like hotel bookings to ensure that they are relevant.

The new ads are interactive and visual and are built for specific markets. For example, there are ads for car sellers, which give something of a tour of the car. The new ads for hotels give prices and availability, allowing users to easily book rooms.

The shift in the market isn't necessarily a good one for Google, however, it is one that it has to deal with nonetheless. The company's growth has suffered because of the fact that ads on mobile bring in less than ads on desktop. While it is coming up with ways to make the shift easier and mobile ads are getting a little more expensive, it is becoming clear that other platforms, such as Facebook, are taking a lot of mobile traffic.

The changes in the search industry have been gradual but clear, starting back in 2007, when Apple first unveiled the iPhone and when mobile search first became a prominent idea. Google is one company that has been able to adapt far more easily because of the fact that it is a search engine and because it is behind the development of the Android mobile operating system.

The news comes shortly after Google announced a tweak in its search algorithm that means that mobile-optimized sites will be promoted more heavily than non-optimized sites on mobile devices. The likes of Facebook and Twitter have also been making big changes to their algorithms and offerings in order to better advertise on mobile.