Google’s recent launch of a beta version of Google AdSense for Mobile Applications brings new opportunities for advertisers to profit from the expansive, yet untamed realm of mobile marketing. Until recently, mobile marketing was limited to opt-in text messages, banner ads on WAP-generated web pages, and paid search ads. That’s changing with the recent uptake of smartphones. Research firm Gartner  indicated smartphone sales to end users represented 13.5 percent of worldwide mobile device sales in the first quarter of this year, up from 11 percent in the first quarter of last year. And Gartner predicts that the mobile advertising market will grow from approximately $3 billion in 2008 to over $12 billion by 2011. Through its current AdWords interface, Google provides targeting functionality to identify iPhone and smartphone customers. This enables advertisers to create unique mobile campaigns with targeted landing pages and one-click calls to action, such as text and phone calls. Advertisers can also serve ads based on the location of one’s mobile phone. The popularity of smartphones, combined with Google making it so easy to customize and serve ads to customers on the move, will likely drive a good portion of this expected growth in mobile. But Google, very quietly, announced another component of its mobile monetization strategy -- text and image ads served with mobile applications. This inventory has been dominated by AdMob until now, but Google brings a huge advertiser base with self-service and easy opt-in. With more than 1 billion Apps downloaded from the iTunes App Store, there is a lot of inventory out there waiting for just such an easy in. I recently authored an article in iMediaConnection entitled “Google’s Role in Finding Mobile’s Tipping Point ” to consider the possibilities and potential of targeted advertising in mobile applications. Have a look and let me know about your experience with mobile advertising as it exists today, and whether or not AdSense for Apps will be an inflection point in the growth of this channel.