Kaasinen, Eija

VTT Information Technology, Sinitaival 6, P.O.Box 1206, FI–33101 TAMPERE, Finland

VTT Publications 566, May 2005, 151 p. + app. 64 p. [in English]
ISBN 951–38–6640–8 (soft back ed.)
ISBN 951–38–6641–6 (PDF edition)

Keywords: mobile services, user acceptance, Technology Acceptance Model, human-centred design, mobile Internet, location-based services, value, ease of use, usability, trust, ease of adoption

Abstract

This dissertation studies user acceptance of mobile services based on a series of case studies of mobile Internet and location-aware information services targeted at consumers and accessed mainly by mobile phones. The studies were carried out in connection with technology research projects, where the objectives were to develop technical infrastructures, to pilot the technology in demonstrator services, and to collect user feedback in field studies to assist in focusing future commercial deployment of the technology. A Technology Acceptance Model for Mobile Services is proposed on the basis of the results of the case studies. According to the model, user acceptance is built on three factors: perceived value of the service, perceived ease of use, and trust. A fourth user acceptance factor: perceived ease of adoption is required to get the users from intention-to-use to actual usage. Based on the Technology Acceptance Model for Mobile Services, design implications for each user acceptance factor are proposed.

Instead of implementing collections of useful features, the design of mobile services should be focused on key values provided to the user. The value of mobile services can be built on utility, communication or fun. Successful service content is comprehensive, topical and familiar, and it includes personal and user-generated content. The users appreciate seamless service entities rather than separate services. Ease of use requires a clear overview of the service entity, fluent navigation on a small display, and smooth user interaction with the service. The users should get personally and situationally relevant services and information without needing to expend effort on personalisation. The services should be designed to be adaptive to the wide variety of devices and networks. As the services increasingly support individual users in their daily tasks and the services are increasingly dealing with personal data, user trust in the services is becoming more and more important. The user should be able to assess whether (s)he can rely on the service in the intended contexts of use. The user needs to feel and really be in control, and the privacy of the user must be protected.

Occasional usage and momentary usage sessions on the move are typical of mobile services. In addition, services are increasingly available only locally or in certain contexts of use. This indicates the need for disposable services: services that are easy to find, take into use, use and get rid of when no longer needed. The user needs realistic information about the actual values of the services, so that (s)he can realise how to utilise the service in his/her everyday life and to innovate new usage possibilities.

Designing mobile services that will be accepted by users calls for changes also to the design methods. Value-centred design aims to identify the key targeted value(s) for end users, service providers and other stakeholders, and then focuses on these values in the design. The proposed Technology Acceptance Model for Mobile Services provides a tool to communicate key user acceptance factors and their implications to the design.

Contents

Abstract
Preface
Acknowledgements
List of original publications
1. Introduction
2. Mobile technologies
2.1 Mobile networks
2.2 Mobile handheld devices
2.3 Positioning techniques
2.4 Summary
3. Human interaction with mobile devices
3.1 Mobile contexts of use
3.2 User interaction with mobile devices and applications
3.3 Mobile usability
3.4 Personalisation
3.5 Context-awareness
3.6 Summary
4. Mobile service concepts – history and future visions
4.1 Mobile Internet
4.1.1 Wireless Application Protocol (WAP)
4.1.2 i-mode
4.1.3 Mobile Internet usability
4.2 Location-based services
4.3 Mobile service business
4.3.1 Mobile service markets
4.3.2 Business models for mobile services
4.4 Future visions of mobile service concepts
4.5 Challenges to user acceptance of mobile services
5. Related research
5.1 Approaches to study user acceptance of technology
5.1.1 Human-centred design process
5.1.2 Technology Acceptance Model
5.1.3 Innovation Diffusion Theory
5.1.4 Hype cycle of technologies
5.2 Studies on user acceptance of mobile devices and services
5.3 Applicability of current approaches to studying user acceptance of mobile services
6. The research framework
6.1 The research approach
6.2 Technology Acceptance Model for Mobile Services
6.3 The case studies
7. Design implications for user acceptance
7.1 Perceived value
7.1.1 Successful service content is comprehensive, topical and familiar
7.1.2 The service should provide personal and user-generated content
7.1.3 The users appreciate seamless service entities rather than separate services
7.1.4 The services need to provide utility, communication or fun
7.1.5 Summary
7.2 Perceived ease of use
7.2.1 Clear overview of the service entity
7.2.2 Fluent navigation on a small screen
7.2.3 Smooth user interaction with the service
7.2.4 Personally relevant services and information without expending effort on personalisation set-up
7.2.5 Easy access to situationally relevant information and services
7.2.6 Facilitating momentary usage sessions on the move
7.2.7 Context–aware multimedia access
7.2.8 Design for device and network variety
7.2.9 Summary
7.3 Trust
7.3.1 The user should be able to rely on the service in intended contexts of use
7.3.2 Measurement without estimated accuracy is of no use
7.3.3 The privacy of the user must be protected even if the user would not require it
7.3.4 The user needs to feel and really be in control
7.3.5 Summary
7.4 Perceived ease of adoption
7.4.1 Real values of the services need to be emphasised in marketing
7.4.2 Disposable services for occasional needs
7.4.3 The service has to support existing and evolving usage cultures
7.4.4 Summary
7.5 Summary of design implications
8. Service providers' point of view
8.1 The hype and flaw of mobile Internet
8.2 Integrating business networks for location-aware services
8.3 Future challenges for mobile business models
9. Implications for usability design and evaluation methods
9.1 Wider views of the human-centred design process
9.2 Towards value-centred design
9.3 Adapting to faster development processes
9.4 From laboratory to the field
10. Conclusions and discussion
10.1 Back to the research questions
10.2 What could have been done otherwise
10.3 Future directions
References
Appendices

Figures and Tables

Figure 1. Mobile phone, communicator and PDA.

Figure 2. The difference between a mobile phone and a PDA is getting more blurred, as phones are equipped with larger screens. The numeric keypad is still typical of mobile phones.

Table 1. Mobile phone user interface elements for user input and for output to the user as described by Kiljander (2004).

Figure 3. Main user interface elements on a mobile phone (Nokia 6600).

Figure 4. Nielsen's definition of usability as part of acceptability (Nielsen, 1993).

Figure 5. Mobile phone usability knee (Kiljander, 2004).

Figure 6. Some of the first WAP phones by Ericsson, Nokia and Siemens. The same service looked and felt quite different on different WAP phones.

Figure 7. On media phones colours and images can be utilised in services (Sonera Plaza, wap.sonera.fi).

Figure 8. Two early i-mode phones.

Figure 9. Mobile phone usage for different purposes in six European countries (Pittet, 2004).

Figure 10. Usage of mobile data in Japan (Liew et al., 2004).

Table 2. Wireless business roles (Kallio, 2004).

Figure 11. An example of the mobile value chain for entertainment services (Funk, 2000).

Figure 12. Human-centred design process (ISO, 1999).

Figure 13. Technology Acceptance Model (Davis, 1989).

Figure 14. Enhanced Technology Acceptance Model (TAM2) by Venkatesh and Davis (2000).

Figure 15. Unified Theory of Acceptance and Use (Venkatesh et al., 2003).

Figure 16. Innovation adopter categories (Rogers, 1995) with the chasm as defined by Moore (1999).

Figure 17. The hype cycle (Linden and Fenn, 2003).

Figure 18. The relative timing of the hype cycle and the Innovation Diffusion (adoption) curve together with the rising curve of technology performance (Linden and Fenn, 2003).

Figure 19. The basic concept underlying user acceptance models (Venkatesh et al., 2003).

Figure 20. VTT's human-centred design approach.

Figure 21. Technology Acceptance Model for Mobile Services as an extension and modification of TAM by Davis (1989).

Figure 22. Our mobile Internet solution converted Web content to WML and adapted the presentation according to each individual client device using the User Agent Profile (UAProf) that defines device characteristics and user preferences.

Table 3. Overview of the services studied, research methods used and users involved in each paper.

Figure 23. The shift from common to personal increased the appeal of the services.

Figure 24. On a small screen, there is a lot to scroll, even when accessing a simple Web page.

Figure 25. Images were converted and put behind links on WAP phones.

Table 4. Trade description model for personal navigation products and services (Kaasinen et al., 2002).

Figure 26. Architecture of NAVISearch location-aware integrated directory service.

Table 5. The business roles in NAVISearch location-aware integrated service directory.

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