Mobile: Potential to revolutionize advertising?

In its very fundamental terms ideal advertising is about giving the person what he wants, when he wants. Google made billions of dollars by make a leap towards this, offering people what they were searching for. Something seemingly as simple as narrowing whom to target upturned the whole online advertising marketplace and allowed Google to something that is producing several billion dollar annually and is growing at an even phenomenal pace. But lets consider for a second, "How big is the online marketplace as compared to the physical marketplace?" Without even thinking twice anyone could come up and say "really small". How is any company supposed to upturn this industry by allowing advertisers to give physical shoppers what they want, when they want? The only answer I can think of is some set of services accessible via a mobile phone.

Mobile is the only device that allows a person to always stay connected with the networked world all the time, everywhere. In other words, it is the only device with a potential to connect the physical world to the smart virtual world full of tons of information, relevant advertisements and what not. Being a doorway to access information also makes it the doorway for advertisers to offer relevant adverts to potential customers in a purely physical setting. For instance, my friend Lisa sitting in her car and looking for a "Gas station", can simply search for that using her mobile phone and can be pushed relevant advertisements such as from shell offering her a discount of 5%, if she takes the effort to drive an extra mile to get his/her tank refilled from their Gas station on Broadway. She reaches the station snaps enters her discount code and gets the promised discount, additionally, she also gets 100 points for the purchase and is now a part of the Shells customer loyalty program. Lets consider another example: I enter best buy planning to buy a TV, my phone can start pushing me a comparative specifications for each TV set as I pass them and offer special adverts making me wanna buy one particular TV set vs. the other. Furthermore if I want to do compare amongst the 5 sets of TV I like, I can simply give a print command and can visit the customer service counter to collect a table showing the feature set comparison of those (very similar to what I can do on Amazon today). Extending this example slightly further, consider the possibility of my phone being like a wearable internet which offers me the relevant services wherever I go, for instance in this case an application can automatically start showing me the details of deals available in the store when I enter and stops showing that as soon as I leave the store.

There are hundreds of possibilities for entrepreneurs to take this challenge and make something that is several times more stronger than what Google did to the online advertising world. The biggest challenge in my opinion is to make such compelling applications usable on this small device such that it doesn't look like a spam but a service. Any takers?