In the last four years the growth in the number of mobile telephone users worldwide has exceeded the growth in the number of fixed lines, expanding from 50 million to almost one billion in 2002. Today over 90 percent of countries have a mobile network, and nearly one in every six of the world's inhabitants has a mobile telephone. Almost 100 countries have more mobile than fixed-line telephone subscribers. Mobile Commerce (m-commerce) is part of this explosion and opens up a myriad of options for new electronic services and new usage scenarios of mobile devices. Fundamental to a rapid expansion of m-commerce is improved access to mobile services. There are several challenges to make this happen including intelligent user interfaces, capturing user's context, privacy and security issues, quality of service, interoperability, semantic of Web and Web services, domain specific ontologies, industrial strength inference mechanisms, middleware technologies for mobile systems, and geographic information services, to name but a few.
The guest editors would like to thank the authors who submitted papers in response to the call for papers. 10 submissions were received, 4 of them were accepted after a careful review process. The first paper, authored by S. Avancha et al., presents the design of a flexible middleware system for m-commerce in pervasive environments. The suggested middleware integrates concepts from the Contract Net protocol, semantic service discovery, and protocols to secure transactions, to ensure the integrity of the received goods, and to protect information against misuse. For validation purposes, the middleware has been implemented and has shown the validity of the suggested concepts. The second paper, authored by S. Ying Ho and S. Ho Kwok, talks about the increasing role of offering personalized services to users of mobile commerce. An empirical study has been conducted and has shown that acquiring new customers could be performed through personalized services. The study has considered four elements, among them the usefulness of general advertisements and the privacy issues of personalized advertisements. The third paper, written by V. Zeimpekis et al., compares different indoor and outdoor positioning techniques to locate mobile devices. The authors classify current and future mobile location-based services and match them with the appropriate positioning techniques, in particular considering the accuracy required for a certain class of services. The last paper, authored by T. Pilioura et al., explores different settings to support web services on mobile devices, comparing their respective advantages and drawbacks.
The guest editors would like to thank the following people for their time and efforts to review submissions. Their comments of changes and suggestions of improvements to authors have helped a lot in shaping the content of the current issue on m-commerce. These people are: G. Al-Khatib (Qatar), M. Berger (Germany), A. Bhati (UAE), B. Burg (USA), P. Doran (UAE), M. Dumas (Australia), O. N. Hamali (Turkey), D. Hobbs (UK), Y. Kabak (Turkey), A. Kamel (USA), S. Kirbas (Turkey), B. K_nig-Ries (Germany), G. B. Laleci (Turkey), A. Lansari (UAE), Q. Mahmoud (Canada), W. Mansoor (UAE), S. Mellouli (Canada), A. Messer (USA), G. K. Mostéfaoui (Switzerland), S. K. Mostéfaoui (Switzerland), H. N_sekabel (Germany), O. Ozdikis (Turkey), O. Ozturk (Turkey), S. Pektas (Turkey), W. Shen (Canada), Q. Z. Sheng (Australia), S. S. Sinir (Turkey), A. Tumer (Turkey), H. Yahyaoui (Canada), and A. Yildiz (Turkey). Finally, the guest editors would like to thank P. Wurman, Editor-in-Chief of the SIGecom Exchanges Newsletter, for his guidance.