The television allowed companies to send ads directly to consumers' living rooms, and the computer allowed them to start interacting with their customers. The third screen-the mobile device-changes the game in an even more radical way. The birth of m-commerce is not just about using the phone to pay for something. It is revolutionising the entire buying process based on location. Marketing has now become hyper-local. Author Chuck Martin explains how in this, the age of the smartphone - and now the tablet - the nature of marketing is changing as well, creating a new system of participatory advertising in which 'untethered' customers and forward-thinking companies must exchange valuable information within 'the cloud.' In Singapore, for example, a mobile app has been developed that maps the insides of shopping malls so advertisers can target customers based on their exact location and shopping habits. M-commerce is also heating up in Europe with Italian and Swedish buyers warming most to the idea. Regardless of where buyers are located, or whether they're purchasing or just browsing, companies need to come up to speed on how to reach them. This essential guide allows businesses to keep up, and soar ahead, in the new world of m-commerce.