Interactions through the mobile phone make a deeper connection with a customer, and a more valuable impression. Once you factor in mobile's low cost of creation and high response rates, you realize the true return on your investment compared to other forms of advertising. It has become part of a mobile campaign to look for added benefit from participants sharing messages and forwarding mobile offers to friends. This viral activity lifts participation to further increase the ROI of your program. By building this into your campaign through the design of programs that track and reward participants who forward ads and offers to friends and build buddy lists, you can start with the smallest database that will exponentially grow within weeks.

Brands aimed at the youth market have had particular success in gaining responses and insights by text. BBC Radio 1 ran a Ten Hour Takeover on Easter Monday in 2004, which generated 150 000 responses from listeners telling the DJ what music they wanted to hear. The most popular choices were played live on air during the ten-hour period.

Another example is that of a well-known hairdressing brand that was opening its 287th salon in the UK. The particular problem in this instance was that the business had no track record, but the brand had significant recall. We tried a small test, offering the first 20 people to arrive at the salon on opening day free haircuts, and a further 50 free products. This went out as an SMS to...