20 PERVASIVEcomputing Published by the IEEE CS and IEEE ComSoc ■ 1536-1268/05/$20.00 © 2005 IEEE

T H E S M A R T P H O N E

Enabling PervasiveComputing with Smart Phones

Mobile telephony’s technical and market success in Europe in the early 1990s attractedresearchers’ interest in mobilesystems. Some researchers began

investigating appropriate architectures for provid-ing information services to cellular mobile tele-

phony users, and the quest forthe “killer” third-generation(3G) mobile telephony applica-tion dominated the EU Informa-tion Society Technology researchprogram from 1998 to 2002.Dozens of projects launched topursue this aim, and we wereintimately involved in several ofthem. We report here on lessonslearned during our involvement

in this research and suggest how pervasive com-puting might benefit from this experience.

3G and beyondA common thread throughout this work is the

desire to develop universal information servicesdelivered over ubiquitous, high-speed wirelessnetworks. While the second generation of mobilecomputing is largely a person-to-person voice(and increasingly short messaging) communica-tions medium, 3G visions add data services andcorresponding infrastructures to support serviceprovision. But 3G didn’t arrive as expected—today, mixed 2G, 2.5G, and 3G networks oper-

ate alongside local wireless networking systems,most based on Wi-Fi and Bluetooth protocols.Research focus has thus shifted to what’s cur-rently known as fourth-generation (4G) orbeyond-3G (B3G) mobile networks, seen as anextension of the current situation. In many ways,the current assumptions of the European Infor-mation Society Technology research program(running until 2006) resemble those proposed inthe US as ubiquitous or pervasive computing.Considerable differences exist, however—forexample, regarding the appropriate developmentpath for such infrastructures.

Also driving this shift in program priorities isthe realization that miniaturizing sensing andcomputational devices allows for deeply embed-ded wirelessly networked systems. Ambient intel-ligence—the vision for the European InformationSociety Technology program’s next 15 years1—resembles pervasive or ubiquitous computing, butit emphasizes the system infrastructure’s auto-nomic learning capability and interaction mech-anisms for users in particular social contexts. Itsultimate aim is to populate the environment withsmart devices and make information servicesaccessible everywhere.

Developing mobile telephony information ser-vices poses several ubiquitous computing chal-lenges. The very small form factor complicatesuser interaction, and devices might operate ininsecure or even hostile environments. Also lack-ing are reliable network connectivity and infra-

Although some business and practical challenges exist, mobile phonescould serve as information service end points, control devices forubiquitous systems, network hubs for personal and body area networks,and ID tokens.

George RoussosBirkbeck College, University of London

Andy J. MarshVMW Solutions

Stavroula MaglaveraPouliadis Associates

structures that support service delivery.However, currently available servicedelivery techniques for mobile and PDA-type smart phones’ small form factorshould prove useful for similar devicesused in pervasive systems. Some researchon mobile information services provisionexplores voice as the primary interactionmodality. (A review of methods andresults appears elsewhere.2) Because peo-ple frequently carry mobile phoneswherever they go, distinct opportunitiesexist for harvesting profile and activitydata and for delivering timely informa-tion services. Finally, many mobilephones currently feature wireless localnetworking capabilities that let theminteract with other nearby devices.

Perhaps most importantly, pervasivecomputing and mobile telephony sys-tems operate in significantly differentenvironments.3 Whereas most pervasivesystems inherit the Internet’s legacy ofopen standards and systems and end-to-end application architectures, mobilephones operate within a more restrictedenvironment. This offers distinct secu-rity advantages because the telephonynetwork operator has greater controlover management operations, but thisenvironment’s clear separation of datatransfer and control planes potentiallyleads to a fundamentally different ser-vice architecture.

Mobile phones as informationservice end points

From the pervasive computing perspec-tive, the mobile phone’s most interestinguse is as an end point for an informationutility or service. Indeed, ubiquitous infor-mation delivery is one of the most oftendiscussed scenarios of pervasive systems.

Popular scenarios include spatial navi-gational assistance and recommenda-tions for nearby places of interest, shop-ping, and entertainment; task-specificcognitive assistance; access to personalmessaging and schedule information;and health care monitoring and diagno-sis. The pervasive computing vision dic-tates that such services should be acces-sible from any location and wheneverneeded, via various devices augmentedwith computational and communica-tions capability.

The literature discusses several devicetypes supporting such interaction, rang-ing from ambient displays to tangibleinterfaces and more traditional appli-ances. Despite their considerable advan-tages, such devices are expensive and notwidely available. Mobile phones offer ashort-term solution readily available tomuch of the global population at rela-tively low cost. Moreover, their currentcomputational capabilities comparefavorably with common mobile applica-tion requirements and also against sev-eral device types often used in pervasivecomputing. Finally, today’s mobile phonenetworks provide an almost global ubiq-uitous wireless access network, whichsatisfies most requirements of pervasivecomputing information service delivery.

Mobile phones’ advanced processingcapabilities offer many opportunities fordeveloping novel information services.Although some of these can be deliveredby voice, smart phones support moreadvanced interactive user interfaces. Sev-eral projects we’ve been involved withaimed to develop such services:

• mXpress4 exploits location sensingand tracking to provide navigationalassistance within a trade exhibitionspace. The system lets preregisteredusers who’ve provided personal pro-files receive targeted content, such asnotifications about specific events ofinterest (http://mexpress.intranet.gr).

• MyGrocer,5 a 2G pervasive retail sys-tem (see Figure 1), includes a shoppinglist management and order placementclient for smart phones (www.eltrun.aueb.gr/mygrocer).

• E-Care6 developed a data-harvestingsystem to collect patients’ vital mea-surements and provide a care-in-the-community monitoring and alertingservice for people with chronic condi-tions (www.e-care-ist.net).

• TellMaris,7 shown in Figure 2, employslocation sensing to display 3D maps,overlaid with tourist information(www.tellmaris.com).

APRIL–JUNE 2005 PERVASIVEcomputing 21

Figure 1. MyGrocer uses radio frequencyID technology to tag supermarket objectsand monitor consumption patterns. One of the applications developed forsmart phones lets clients manage theirshopping lists and place orders while onthe move.

These projects all need to provide con-textualized information. In this case,context refers to both the user’s cogni-tive context and the system’s operationalcontext (such as available wireless band-width). Personal context information letsus minimize the number of steps requiredto carry out a specific action, and this inturn depends on adapting content andapplication functionality.8 Unlike desk-top systems, where functionality oftentakes precedence over speed, mobiledevices’ small form factor and limitedinput facility (mostly a numeric keypadand in a few cases an Accupoint or point-ing stick) lessen the chances that userswill complete tasks requiring a long inter-action sequence. More common meth-ods to develop personal context modelsinclude extracting common patternsfrom demographic and historical usagedata, which the system then uses to antic-ipate user actions or better meet userinformation requirements.

We can further improve the successrate of predicting what users will chooseif we also consider their current situa-tion. For example, we can use locationand time-of-day information to identifyspecific user activities and roles, per-mitting faster access to specific contentor appropriate application functional-ity configuration. Such mechanisms canbe inaccurate, however, and we shoulduse them conservatively and in additionto rather than instead of other systemfeatures that help users perform tasksefficiently. Indeed, a common pitfall isto optimize aggressively for user inter-action. When the system predicts the

wrong pathway or, even worse, preventsthe user from accessing required func-tionality because it doesn’t appear to bea probable alternative, the user willmore likely reject the system than if heor she only had to deal with the diffi-culty of navigating the interface.8

Finally, we can also adapt services tomeet system capabilities, primarily interms of user interface features and avail-able network bandwidth. For example,the user experience suffers if the systemdelivers rich content developed for a 3Gnetwork over a slower network segmentthat supports only GPRS, because per-formance will likely be inadequate.

In recent years, the priorities in per-sonalizing mobile information serviceshave shifted considerably. The originalstated goal was to make information ser-vices available to anyone, anywhere, atany time. But in practice many haveinterpreted this aim as providing every-one, everywhere, all available informa-tion all the time, leading to cognitiveoverload and service failure. For exam-ple, with mXpress we found it relativelyeasy to make massive amounts of infor-mation available to exhibition visitors,but users often had difficulty makingsense of this information without appro-priate means to organize and track data.4

Today, personalization focuses on cre-ating information services that deliverthe right information at the right time,in the right place, in the right way, to theright person. Indeed, in a world satu-rated with mobile information services,providers compete not to distribute mas-sive amounts of information but rather

to gain the user’s attention. Earlyattempts to develop information ser-vices for mobile phones assumed thatmobile users were simply “mobile Inter-net” users. Services thus aimed to repro-duce the desktop Internet browser expe-rience, albeit with a more compactinterface and less demanding data trans-fer requirements.

This view has proven erroneous—information services on the move play afundamentally different role and cannotbe developed just by trivially extendingthe desktop paradigm. Web navigationhighlights the difference between desktopand mobile devices: desktop users canemploy a search engine to retrieve severalpages of relevant results and review themin turn, moving from site to site over time.This is hardly feasible for mobile users,who should be taken directly to a specificlocation to carry out a short, focusedtask.9 Mobile information services mustbe designed specifically for the context oftheir use and meet mobile users’ needs forbrief, targeted sessions.

This application-layer property extendsbeyond the user interface and the appli-cation functionality to the service archi-tecture itself. The requirements ofbrowsing Web pages on a mobile phonego well beyond the need to display con-tent in a condensed form. The contentitself must be modified to meet userexpectations and needs, and moreimportantly to match user activities. Forexample, we found in a recent study thatthe British Museum’s Compass, anextensive online database for objects inits collections, wouldn’t meet mobileusers’ needs during museum visits. Com-pass pages often provide lengthy back-ground discussions of objects and exhi-bitions that require users to switch fromthe visit’s physical and social context tothat of information browsing on the

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T H E S M A R T P H O N E

Figure 2. The TellMaris client applicationinterface lets users navigate a 3D modelof their location and discover nearbylandmarks and services.

device. This attracts attention away fromthe visit’s main focus in a fairly disruptiveway. Typically, mobile users want a con-cise overview of objects, and relevantpages should present the information ina less academic, more informal style bet-ter suited to the visit’s discursive nature.Although automated summarizationtechniques might help here, a personshould author or edit mobile user con-tent to achieve the desired effect.

Likewise, TellMaris showed that thelocation itinerary dominates tourist vis-its, and a complex information serviceinterferes with the actual experience.More appropriate and desirable is a sim-ple but authoritative response to a loca-tion-specific query or notification of achange in environmental condition.7

The finding that content should beauthored specifically for mobile users’activities suggests that transcoding archi-tectures developed in various mobilecomputing projects are less importantthan initially thought. Although thisfunctionality is clearly feasible and in factis now readily available in commercialplatforms, it addresses a problem thathas minor implications for a system’ssuccess. Of course, achieving interoper-ability between devices of the same formfactor is clearly desirable and should beaccommodated whenever possible. Butthis finding may have design implica-tions for some emerging pervasive com-puting infrastructures. Content authoredfor a smart phone might be inappropri-ate for users interacting with tangibleinterfaces or proactive displays, anddesign principles developed for mobiletelephony might not transfer well tothese situations.

Mobile phones as remotecontrollers

Pervasive computing requires theseamless interoperation of diverse devicesand electronically augmented artifactswithin spaces saturated with wireless

communications capability. In the homeenvironment, for example, perhaps hun-dreds of (mass-produced) devices mustbe configured and managed to operatein a way that satisfies the needs of thefamily occupying this space. Althoughthe pervasive computing vision dictatesthat such devices adapt automatically,current techniques cannot robustly andconsistently support this on a large scale.The mobile phone offers a potential solu-tion by acting as a control device, simi-

lar to remote-control devices used inconsumer electronics.10

This approach faces several challenges,not least the limited availability of stan-dards that are clearly essential for its suc-cess. Yet the concept has appeal in thatthe mobile phone fits this role well. Smartphones’ processing capability permitsflexible functionality that can be adaptedor extended to include control functionsfor particular devices. Larger-form-fac-tor smart phones allow for the provisionof more intuitive user interfaces, such asa physical space abstraction to controlmultiple devices simultaneously or inter-pret higher-level commands to device-level management functions. Instructionscan be transferred locally using a wire-less interface. In fact, although infraredcommunication is relatively low band-width and is often discounted in perva-sive computing systems in favor ofhigher-power access media, we’ve foundit well suited to this role and a potentiallyappropriate solution.6 Naturally, a mobiledevice also offers the opportunity to man-age the home environment remotely, forexample, via a control applet that con-

nects directly to an Open Services Gate-way home server.11

We see another, more subtle advantageto using the mobile phone as a remotecontroller in a pervasive computing sit-uation. Ubiquitous computing systemsusers often have difficulty conceptualiz-ing the system and thus developing men-tal representations and appropriatestrategies for interacting with it.12 Theproblem is that system functionality istransparent, and unlike other comput-

ing situations, ubiquitous systems offerno specific interaction point. People areused to interacting with information sys-tems via specific service end points, suchas a personal computer, a bank tellermachine, a digital television, or a mobilephone. Ubiquitous computing is, asMark Weiser put it, “invisible, every-where computing that does not live ona personal device of any sort, but is inthe woodwork everywhere.”13 It thushas no specific physical expression. As apoint of contact, the mobile phonebecomes a manifestation of the perva-sive service and thus much easier to con-ceptualize and interact with.

Mobile phones as pervasivenetwork hubs

We find a more interesting use ofmobile phones in pervasive computingwhen considering their functionalityrather than their form, that is, as a com-munications device offering wide-areanetworking capabilities. The cellulartelephone can operate as the hub of apersonal or body area network: it con-nects to remote services and the Internet,

APRIL–JUNE 2005 PERVASIVEcomputing 23

Smart phones’ processing capability

permits flexible functionality that can be

adapted or extended to include control

functions for particular devices.

and the local area network connects tolocal devices.

The Healthcare Compunetics archi-tecture offers one incarnation of this con-cept.14 It specifies a system that processesdata harvested from sensors into anappropriate XML-based specificationcalled i-notes. It stores them for futureuse and, following a predefined policy,communicates them to the appropriateconsultant for analysis. Because connec-tivity with health care systems might not

always be available, Healthcare Com-punetics provides two devices that worktogether to offer secure storage andseamless communication within a bodyarea network. The first component is thei-wand, a wearable storage and process-ing device with fingerprint authentica-tion. It structures and stores personaldata in i-note format, checks it on the flyfor evidence of critical conditions locally,and encrypts it. The device employs wiz-ards that detect the type of sensor that’stransmitting data, and it currently sup-ports many homecare monitors, flat-padded water-resistant hypoallergenicdermal patches, and certain biocompat-ible sensor chips in ingestible capsules.The second component, the Mobiliser,is a GUM (Global System for MobileCommunication) modem core attachedto the i-wand that communicates withback-end servers over the cellular net-work. These two devices transform themobile phone into an enabling device fortypical ubiquitous information services,removing the recognizable form of thedevice itself.

This approach removes the mobile

phone’s form factor limitations and,taken to its extreme, lets us see thewhole personal area network as anextended telephone. This view suggestsseveral similarities between mobilephones and more typical pervasive com-puting devices. For example, EriccsonResearch Labs’ Phone Glove15 intro-duces the idea of a fragmented tele-phone consisting of a basic communi-cations core embedded in user clothingand the remaining components distrib-

uted to the points of their actual use. Wealready see a form of this when peopleuse an earphone instead of the mobilephone speaker. This model would alsosupport electrical field sensing and thefinger-joint gesture keypad input para-digm to replace the traditional telephonenumeric pad. Phone Glove uses the fin-ger phalanges as the telephone keypadand the thumb as operator.

Other projects take a similar approachto provide wide area connectivity forwearable systems. In some cases, the tele-phone core transmits data harvestedfrom associated sensors in the body areanetwork; in other cases, the device actsas a network router to receive informa-tion from a remote location and passesthe content along for further processingor display at another network compo-nent. By accessing remote services andthe Internet, these systems can employnetwork-based authentication andauthorization processes and thus par-tially address the problems of secureoperation and privacy protection inher-ent in all pervasive computing environ-ments. In fact, some see smart phone

cores as the basis for developing a net-working model for ubiquitous comput-ing based on user-centered concentricspheres—for example, the Multi-SphereReference Model,16 a current proposalof the Wireless World Research Forum.

Mobile phones as ID tokensArguably, one of the most pressing

challenges in pervasive computing is secu-rity and privacy protection.12 Mobilephones can address this challenge by act-ing as a secure personal device that storesinformation used to verify user identityand determines when to disclose thisinformation. This generalizes a functionthat all mobile phones carry out undernormal circumstances. For example, ona GUM network, they use their embed-ded unique ID code and the GUM fam-ily of cryptographic algorithms to iden-tify users to the network and verify theirright to access resources and services.

The mobile phone can also store cre-dentials associated with specific infor-mation services—for example, electroniccommerce account logins and paymentinformation using the Electronic Com-merce Modeling Language, which sev-eral mobile phone manufacturers cur-rently support.17 These credentials serveto authenticate with remote services overthe cellular network or over the local net-work by directly interacting with thepayment facility using, for example,Bluetooth or RFID. NTT DoCoMorecently introduced the latter option as acommercially available system in Japanunder the FeLiCa brand.

User ID mobility poses several otherchallenges.17 Identity is mobile betweendevices, between locations, and betweenroles and contexts. Although mobilephones can support some of thesemodes, they are less effective with oth-ers. For example, location mobilityentails coordinating authority domains,because a person moving between loca-tions is also usually moving between

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Some see smart phone cores as the basis

for developing a networking model

for ubiquitous computing based on

user-centered concentric spheres.

areas controlled by different organiza-tions. When a company’s employeesaccess information systems from theirdesks, both the access medium and theinformation storage are physicallylocated within a single authority domainregulated by their employer. But whenthey access information via a tradingpartner’s extranet, they cross organiza-tional boundaries, and the trust rela-tionship between the two organizationsmust be negotiated as well.

Clearly, smart phones can provideonly a partial solution to this problem.Role and context mobility is even harderto address, and a mobile phone proba-bly can’t provide either the computa-tional power or the storage resources tomaintain appropriate role representa-tions and predict suitable actions inde-pendently. Of course, the three modesof mobility are not isolated. User actions(active or passive, such as movingbetween rooms) typically modify themconcurrently and thus create much morecomplex situations than what a singlemode implies in isolation. Finally, amobile phone has limited capacity tohold ID credentials because the individ-ual elements comprising the mobileidentity might be distributed betweendifferent locations, authority domains,and devices, often for regulatory or busi-ness reasons.

Business and practicalimplications

Mobile phone use clearly differs fromthat of an open system such as the Inter-net because mobile operators com-pletely control their networks, includ-ing all data flows. This stems as muchfrom historical reasons, given mobileoperators’ evolution from fixed tele-phone network operators and their ten-dency to follow similar models andstrategies, as from differing user expec-tations. Mobile phone users primarilycommunicate by voice, and their expec-

tations are shaped by their experienceswith fixed telephony. The operators con-trol which parties may offer services overparticular networks and under what cir-cumstances, and these parties will gen-erally enter a profit-sharing agreementwith the operator.

Service availability and infrastructures

We must consider what services mightbecome available if pervasive comput-

ing’s network access model follows thatof today’s cellular mobile networks.Indeed, the oft-cited i-mode success storyhinged on the operator’s ability to sharein the profits of third-party providersgiven access to the service. Compare thisto Internet users’ relationship with theirservice providers, who have limited orno control over user choice of consumedservices.

Moreover, many mobile phone systemoperators, including several 3G opera-tors, don’t see information services ascritical for their revenue development.In our work, we’ve often been restrictedby operators that limit data movementon their networks in favor of voice. Onemajor European operator limits GPRS(General Packet Radio Service) users’available bandwidth to well below thetechnology’s capacity, often to a fewKbits. Even more characteristically, theUK’s first 3G operator completely pre-vents users from accessing informationservices and actively promotes a businessmodel in which growth is based on videomessaging. And despite the rapid prolif-eration of Wi-Fi networks, most Euro-

pean operators claim not to be able tosupport a profitable business modelbased on this technology and see it asmerely a value-added service for busi-ness customers rather than a viable pub-lic-access alternative.

The mobile telephony experience todate provides significant lessons for mar-ket development of supporting serviceinfrastructures. Indeed, even if the seam-less interoperation envisioned in perva-sive computing scenarios proves techni-

cally feasible, it might not happenbecause we lack successful business mod-els to support development of the neces-sary infrastructure. Of course, this mightjust be one of the teething problems of awireless communications industry thatdoesn’t yet fully appreciate the opportu-nities pervasive computing offers.

Adapting to user needsWe’ve also learned that we can move

much faster from one technology gener-ation to the next than individuals andgroups can adjust their habits and behav-iors to make new technology part ofeveryday life. This proves especially truein the case of mobile telephony, com-pared to the development of the desktopor the server computer. Whereas previ-ous computing generations used tech-nology primarily for professional activ-ities, mobile telephony offers a morepersonal and intimate computing envi-ronment. As we’ve discovered consis-tently across our work, a mobile phoneis a truly personal device, often seen aspart of an individual’s identity.17

This personal identification makes it

APRIL–JUNE 2005 PERVASIVEcomputing 25

Many mobile phone system operators,

including several 3G operators,

don’t see information services as critical

for their revenue development.

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T H E S M A R T P H O N E

that much harder to demand that usersadopt specific behaviors to operate thetechnology (as is the case for desktopoffice productivity systems). Thus wemust adapt the technology itself to meetindividuals’ needs and self-perceptions.This pressure to develop “calm technol-ogy” will only intensify as we introducedifferent pervasive computing technolo-gies that become part of everyday lifeand, to some extent, invade users’ per-sonal space and intimate activities.

Respecting user privacy and diversity

Finally, ubiquitous computing systemsdevelopment must focus on protectingthe user’s personal data. Retrofittingtrust in any technology is considerablyharder than building it in from the start,especially when users have already per-ceived it as invasive, intrusive, or dan-gerous. In particular, users must under-stand and agree to the rules of ownershipand compensation for data created byuser actions, a core requirement for pro-viding context-aware services. Lack of aclear framework to protect private func-tions or compensate for the use of per-

sonal data will appear unfair and createnegative perceptions of a service.

Developing a substrate for providinguniversal services poses another corechallenge to pervasive computing. Sys-tems must cater to widely varyingnational, cultural, and religious differ-ences, which might result in systemincompatibilities or even the failure ofsuch infrastructures to provide therequired adaptation. Even within aregion with relatively uniform legislation(such as the EU), different countriesmight interpret common rules in incom-patible ways, or in ways that preventprocessing personal data lawfully acrossthe region.18

Our work over the last decadehas sought to make mobileinformation services practi-cal. During this time, our

understanding of the services mobileusers might find valuable has shiftedconsiderably. We anticipate that mobileusers will find the greatest benefit not ina single or a small number of services but

in connectivity itself: always being con-nected to activities, people, and groupsthat play a central role in everyday life.They will interact with services not inlong continuous segments, which arebest facilitated by larger-form-factorcomputing devices, but rather in shortand targeted interactions that fulfill spe-cific needs. Until practical ubiquitousinterfaces and services emerge that allowfor a greater wealth of interactions, thesmart phone will remain the best avail-able personal computing device.

REFERENCES1. N. Shadbolt, “Ambient Intelligence,” IEEE

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2. B. Shum and P. Peterson, “A Data-DrivenMethodology for Evaluating and Optimiz-ing Call Center IVRs,” Int’l J. Speech Tech-nology, vol. 5, no. 1, 2002, pp. 23–37.

3. P. Asunmaa et al., “Introduction to MobileInternet Technical Architecture,” WirelessPersonal Comm., vol. 22, no. 2, 2002, pp.253–259.

4. G. Giaglis et al., “On the Potential Use ofMobile Positioning Technologies in IndoorEnvironments,” Proc. 15th Int’l Conf. Elec-tronic Commerce, Univ. of Maribor Press,2002, pp. 413–429.

5. P. Kourouthanassis and G. Roussos,“Developing Consumer-Friendly PervasiveRetail Systems,” IEEE Pervasive Comput-ing, vol. 2, no. 2, 2003, pp. 32–39.

6. A. Marsh, “The E-CARE Project: Remov-ing the Wires,” Proc. Int’l Conf. ComputerScience, vol. 2, Elsevier Science Publishers,2002, pp. 1012–1018.

7. A. Schilling et al., “Introducing 3D GIS forthe Mobile Community: Technical Aspectsin the Case of TellMaris,” Proc. IMC Work-shop 2003, Fraunhofer IRB Verlag, 2003,pp. 86–92.

8. B. Smyth and P. Cotter, “MP3—MobilePortals, Profiles, and Personalization,” WebDynamics, Adapting to Change in Content,Size, Topology, and Use, M. Levene and A.Poulovassilis, eds., Springer SMB, 2004.

the AUTHORS

George Roussos is a lecturer at the School of Computer Science and InformationSystems, Birkbeck College, University of London. His research interests include ubiq-uitous computing and commerce. He received his PhD from Imperial College, Lon-don. He is a member of the IEEE, the ACM, and the IEEE Computer and Communi-cations societies. Contact him at the School of Computer Science and InformationSystems, Birkbeck, Univ. of London, Malet St., London WC1E 7HX, UK; g.roussos@bbk.ac.uk.

Andrew J. Marsh is CEO of VMW Solutions. His research interests include wearablehealth care devices for vital-signs monitoring and optimization of the HealthcareCompunetics architecture. He is an expert evaluator and project reviewer for theEuropean Commission and a consultant for the European Space Agency. Hereceived his PhD in computer science from the University of Essex. Contact him atVMW Solutions, 9 Northlands Rd., Whitenal, Romsey, Hampshire SO51 5RU, UK;a.marsh@vmwsolutions.com.

Stavroula Maglavera is a research engineer at Pouliadis Associates. Her researchinterests include electronic Internet services, particularly telemedicine. She has aB.Eng. in electrical engineering from the Aristotle University of Thessalonica. Con-tact her at Pouliadis Associates, Nikiforou Ouranou 3, 54627 Thessaloniki, Greece;stavmag@athos.pouliadis.gr.

9. A. Sellen and R. Murphy, “The Future ofthe Mobile Internet,” Appliance Design, no.3, 2001, pp. 7–13.

10. A. Sanguinetti et al., “FReCon: A FluidRemote Controller for a Freely ConnectedWorld in a Ubiquitous Environment,” Per-sonal and Ubiquitous Computing, vol. 7,nos. 3–4, 2003, pp. 163–168.

11. E.A. Gryazin, J.O. Tuominen, and P.Kourouthanassis, “Distributed InformationSystems Development for the ConsumerMarket,” Proc. 2003 Int’l Conf. ArtificialIntelligence Systems (AIS 03), IEEE Press,2003, pp. 88–95.

12. G. Roussos and T. Moussouri, “Privacy,Security and Trust in Ubiquitous Com-merce,” Personal and Ubiquitous Com-puting, vol. 8, no. 6, 2004, pp. 416–429.

13. M. Weiser, “The Computer of the 21st Cen-tury,” Scientific American, vol. 265, no. 3,Sept. 1991, pp. 66–75.

14. A. Marsh, G. Roussos, and Y. Vogiazou,“Healthcare Compunetics: An End-to-EndArchitecture for Self-Care Service Provi-sion,” Proc. 1st Int’l Workshop Body Sen-sor Networks, 2004, www.doc.ic.ac.uk/vip/bsn/home/index.html.

15. M. Goldstein, M.G.O. Baez, and P. Daniels-son, “Employing Electrical Field Sensing forDetecting Static Thumb Position Using theFinger-Joint Gesture Keypad Input Para-digm,” Proc. 4th Int’l Symp. Wearable Com-puters, IEEE CS Press, 2000, pp. 173–174.

16. K. Crisler et al., “Considering the User inthe Wireless World,” IEEE Comm., vol. 42,no. 9, 2004, pp. 56–62.

17. G. Roussos, D. Peterson, and U. Patel,“Mobile Identity Management: An EnactedView,” Int’l J. Electronic Commerce, vol.8, no. 1, 2003, pp. 81–100.

18. O. Pitkänen et al., “Assessing Legal Chal-lenges on the Mobile Internet,” Int’l J. Com-merce, vol. 8, no. 1, 2003, pp. 101–120.

For more information on this or any other comput-ing topic, please visit our Digital Library at www.computer.org/publications/dlib.

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Joe DiNardoPhone: +1 440 248 2456Fax: +1 440 248 2594Email: jd.ieeemedia@ieee.org

Southwest (product)Josh MayerPhone: +1 972 423 5507Fax: +1 972 423 6858Email: jm.ieeemedia@ieee.org

Northwest (product)Peter D. ScottPhone: +1 415 421 7950Fax: +1 415 398 4156Email: peterd@pscottassoc.com

Northwest/Southern CA(recruitment)Tim MattesonPhone: +1 310 836 4064Fax: +1 310 836 4067Email: tm.ieeemedia@ieee.org

Southeast (recruitment)Thomas M. FlynnPhone: +1 770 645 2944Fax: +1 770 993 4423Email: flynntom@mindspring.com

Connecticut (product)Stan GreenfieldPhone: +1 203 938 2418Fax: +1 203 938 3211Email: greenco@optonline.net

Japan (product/recruitment)Tim MattesonPhone: +1 310 836 4064Fax: +1 310 836 4067Email: tm.ieeemedia@ieee.org

Europe (product/recruitment) Hilary TurnbullPhone: +44 1875 825700Fax: +44 1875 825701Email:impress@impressmedia.com

A D V E R T I S E R / P R O D U C T I N D E X

A P R I L - J U N E 2 0 0 5

Charles River Media 8

FIFA 10

Kodak 12

MobiSys 2005 Cover 4

S3i Sound 12

Samsung 11

Sanyo 10

Sony Ericsson 11

SpinVox 10

Toshiba 12

uLocate Communications 10

Boldface denotes advertisements in this issue.

Advertising Personnel

Advertiser / Product Page Number

Marion DelaneyIEEE Media, Advertising DirectorPhone: +1 212 419 7766Fax: +1 212 419 7589Email: md.ieeemedia@ieee.org

Marian AndersonAdvertising CoordinatorPhone: +1 714 821 8380Fax: +1 714 821 4010Email: manderson@computer.org

Sandy BrownIEEE Computer Society,Business Development ManagerPhone: +1 714 821 8380Fax: +1 714 821 4010Email: sb.ieeemedia@ieee.org

Advertising Sales Representatives

IEEE Pervasive Computing10662 Los Vaqueros CircleLos Alamitos, California 90720-1314Phone: +1 714 821 8380; Fax: +1 714 821 4010http://www.computer.org;advertising@computer.org