The last decade has seen incredible growth in the mobile space. Today there are more mobile devices than personal computers and televisions combined: At last count there were 4 billion mobile subscribers worldwide ITU, compared to 1 billion personal computer users. Additionally, with the advent of new, more engaging devices like the iPhone and Android-based devices, shipments of smartphones now equal those of laptops. The large growth in the number of phones, particularly of high-end devices, combined with the availability of affordable flat-rate data plans from phone carriers, is helping to fuel the growth and access to the mobile web.

In the US alone, 50% of people use their mobile devices for more than just voice. The number of people using their mobile device to access news and information on the Internet more than doubled from January 2008 to January 2009 (comScore 09). Looking across desktop and mobile, for the first time in 2009 more than half of all new connections to the Internet will come from a phone (eMarketer, 2008 and 2009).

Not surprisingly, the same trends that are fueling growth in Internet use are also leading to higher search volumes. For example, in 2008 a regional carrier who offered a flat rate plan saw twice the year over year search volume growth as compared to a global carrier that offered per-minute use. Users of the iPhone and the T-Mobile G1 also search much more frequently than users of other devices. The improved mobile browsers and better designed UIs are encouraging users to search and access the web from their phones. Additionally, carriers and OEM's are beginning to surface search in a much more visible way. For example, we've seen about 10X increase in search volumes when carriers have a search icon accessible from the home screen of a device.

While users had once only searched at home and at work, now users are also searching on their phones. Advertisers will want to follow users to this new platform.

Making mobile advertising work

Building the best mobile user experience also means building the best advertising experience -- one in which marketing messages also become useful and actionable information. Whether a mobile user is searching for a nearby restaurant or browsing a favorite sports site, mobile ads should deliver the right advertising message at the right time in the right format, while respecting user privacy.

Mobile advertising should also focus on the same kind of accountability that has been the hallmark of the web and search advertising, complete with the same metrics and conversion tracking that are available today on the desktop. Advertisers will also need to effectively manage their spends and campaigns and being able to oversee and optimize online and mobile campaigns in one single interface will help to provide transparency and measurability for advertisers. And since running a mobile advertising campaign is similar to running an online search advertising campaign, we think advertisers can easily apply the learnings from web search to mobile. The good news is that this platform already exists, with an infrastructure that makes it easy to test and iterate upon advertising campaigns.

In order to take advantage of the mobile medium, advertisers will want to create engaging campaigns that are relevant to consumers. Online advertisers should think about utilizing best practices from the web to create a consistent presence in the mobile medium.

And even as mobile devices are converging toward the desktop and desktop technologies -- something that is happening faster and faster, especially in light of devices like the iPhone and the T-Mobile G1 -- advertisers should think about their customers and how they engage with the mobile experience, asking themselves questions like: How will mobile users interact differently with mobile ads on a mobile device? How might ads look on a cell phone? Is my call to action appropriate for mobile devices? Do I want to only target devices with full browsers where I can use my standard web landing page or should I optimize my landing page for the mobile experience? At what time of day are people searching on their phones? At Google, for instance, search traffic rises on mobile devices on the weekend while desktop search traffic drops. In this way, mobile advertising can be seen as complementary to, and not separate from, an online ad campaign. It allows marketers to extend the reach of their campaigns and deliver the right ad at the right time to users.

The results of mobile advertising are promising

Users are engaging with mobile advertising with high recall numbers. According to the Q4 2008 Limbo GfK US Mobile Advertising Report, one in three consumers that recall seeing a mobile ad state that they responded in some way to the ad. This rises to one in two for iPhone users. (2008 Limbo GfK US Mobile Ad Report).

At Google, we've seen great success from advertisers experimenting in local, retail, entertainment, auto, CPG, and travel -- users simply search for these kinds of things on mobile devices and find the advertisements useful and relevant while they are on the go. By extending their campaigns to the mobile platform, companies in these industries have realized incremental customer acquisition for customers who might not have otherwise located them.

For instance, one of our advertisers, a national pizza franchise, realized that users might be searching for a pizza place while in transit. By running a mobile ad campaign, when a potential customer searches and sees the franchise's mobile ads, she is directed to a simplified iPhone site that provides her with quick links to everything she might need on the go, such as a store locator, an online ordering system, and coupons. This franchise has taken their customer base's behavior into account and has made it easy for users to find a nearby store to buy pizzas, all while gaining new customers in the process.

The shift to mobile has reached a tipping point -- for users it represents a way to interact with information whenever and wherever. As more advertisers begin to adopt mobile advertising, it will be interesting to see what innovations will emerge to create the best possible mobile experience for users while also helping publishers, developers, and advertisers determine the best way to meet their needs on mobile. We think it is important that as an industry we develop tools that provide ads that are relevant and useful to users and give advertisers the ability to effectively manage their cross platform campaigns and provide measurable results.

As we are still in the early days of mobile advertising and best practices still stand to be defined, we think this is a good time to test and learn. Our best contacts in determining this are our advertiser and agencies partners, who can help collaborate with us to create the best product available for their customers. Similar to the early days of online advertising, with more and more consumers accessing the Internet on their mobile devices, we think advertisers should be experimenting and seizing this tremendous opportunity to reach and engage with users on the go.

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