The growing dependency of consumers worldwide on their mobile phones and other portable devices continues to highlight the enormous potential of the mobile channel for marketing purposes. Walking through the world's largest green field music and performing arts festival at Glastonbury, UK, in the summer of 2007 I was struck by the fact that by far the biggest queues were to be found not for the public toilets, but at the orange 'chill "n" charge' mobile phone recharging tent provided by — Orange. Few festival-goers could bear to be cut off from their social networks. The number of mobile connections exceeds the population in an increasing number of markets, driven by the ownership of multiple SIM cards. There is increasing substitution of mobile for fixed-line services, alongside a growth of non-SMS mobile data services and mobile internet driven by the mass market availability of 3G data services.

The development of mobile channels themselves and the attitudes adopted towards them by consumers are, however, fluid and highly unpredictable. We only have to think back 12 months to see the launch of iPhone and of Google Android,¹ both developments that will likely further transform the mobile environment. And while consumers will allow the mobile phone into their personal space, it will not be at any price. The marketer does not have an automatic right to invade that space. Indeed, recent research suggests that younger people find mobile phones attractive just because the text-based and instant messaging allow them to exercise a significantly higher degree of control over interactions than is possible through face-to-face encounters (enabling them to 'stop and think' before having to give a response).²

These uncertainties have not prevented companies from investing in mobile marketing communications. The mobile phone accounts for more than 50 per cent of total telecommunications revenues in all countries examined in a recent OFCOM survey, other than in Sweden and Canada.³ Analysts Berg Insight suggest that revenues from mobile advertising will reach 7.5 per cent of all global advertising spend by 2012 (it is presently an estimated 0.8 per cent).⁴ The techniques available to marketers for their exploitation are evolving and proliferating explosively. Yet demonstrable evidence to support the effectiveness of marketing expenditures in this area proves to be somewhat thin on the ground. And sophisticated mobile users have still tended to receive remarkably unsophisticated and often intrusive communications, by comparison with practice in more mature marketing channels. This special issue of the Journal of Targeting, Measurement and Analysis for Marketing is devoted entirely to measurement issues in relation to mobile marketing.

Michael Becker's opinion piece provides a useful starting point in reminding us that the evaluation of marketing effectiveness is dependent on good data: not just in relation, for example, to handset capability, but also alongside actual consumer adoption of particular handset functions: 'consumers actually report using very few features of their phones'. Indeed, understanding the way in which increasingly complex devices are used by consumers is challenging. Hannu Verkasalo's paper reports on an extensive empirical study of mobile service usage in Finland, focusing on smartphones with extensive functionality. A handset-based approach to research, using a downloadable research client to track usage, does appear to allow distinctive end-user segments to be identified.

Michael Becker's paper also cautions that much data — such as the AdMob advertising metrics — are not yet available on a comparable basis worldwide. Many of the papers within this special issue are deliberately selected from outside the immediate Anglo-American marketing bubble. For example, Süleyman Barutçu maps the generic models of the B2C mobile experience onto the Turkish consumer and finds some interesting differences that are not just linked to different levels of adoption.

Not only within emerging markets but also within mature mobile environments, SMS remains an enormously important mobile communications tool. Behaviours between even mature markets, however, are very varied: over 75 per cent of mobile phone users in France, UK, Germany and Italy send SMS text messages; while in Japan the figure is only 17 per cent, since users prefer email. Alexander Muk's paper examines whether cultural differences between countries (specifically the US and Taiwan) have a significant impact on consumers' adoption of SMS advertising. He concludes that the higher adoption rate of mobile phones in Taiwan does not lead to the Taiwanese consumer being more accepting of SMS marketing messages, because of social influences on usage within a collectivist culture. Thirty-eight per cent of Italian households are 'mobile only' compared to just 10 per cent in Germany and this has led to the growing importance of SMS for political marketing purposes. Irene Prete reviews the effectiveness of these campaigns and reveals that such messages tend to reinforce past voting behaviour, rather than encourage switching.

The use of mobile coupons to stimulate sales and loyalty among consumers has experienced several false starts. One of the most recent schemes to launch in the UK, Shop Scan Save⁵ delivers increasingly personalised coupons to the end user. But in a careful review of the take-up of different forms of mobile couponing in Japan, Fumiyo Kondo and his colleagues point out that the mobile marketer has to work much harder to counter the intangible nature of such offers than for convention coupons: prospective users are simply more likely to forget they have received them, unless prompted!

One way around this is to ensure the delivery of marketing communications in appropriate contexts. Jens Hosbond and Mikael Skov address the possibility that location-based services have to generate more relevant communications that render them more acceptable to consumers. Using a location-aware shopping trolley, their study seeks to demonstrate that users will respond more positively to product-relevant offers. Finally, the continuing extent of innovation within the mobile marketing environment provides the basis of a final paper, from Lieven de Marez and his colleagues, which seeks to identify innovation-prone consumers' adoption processes — in this case, of mobile news and mobile television services. They conclude that what they term new 'mobile communication paths' will need to become available to communicate those messages more efficiently.

Attending the Glastonbury Festival would have been made considerably more comfortable had one of the more innovative mobile marketing developments in the UK been available: the SatLav service from London's Westminster City Council — offering the nearest public convenience in return for texting TOILET to 80097.