Usability analysis and evaluation of mobile ICT systems Asbjørn Følstad, Petter Bae Brandtzæg and Jan Heim SINTEF Telecom and Informatics, PO Box 124, N-0314 Oslo, Norway asbjorn.folstad@informatics.sintef.no Abstract There is a need for new usability methods tailored to suit the development of mobile ICT. In response to this, three methods that have been developed to a prototype level are presented. The methods are designed to be cost-effective and provide information on (1) user problems as experienced in users’ everyday lives, (2) contexts of use, and (3) integration of technology in users’ patterns of activity. The methods have been tried out in a small-scale evaluation in conjunction with the introduction of PDAs and mobile telephones with PDAs in an organisation. Key words: Usability, method development, mobile, ICT, PDA 1 Introduction A major challenge for future usability research is to develop new methods for usability analysis and evaluation of ICT (Information Communication Technology) systems [Abowd & Mynatt (2000); Monk (2000)]. The users of ICT systems are no longer only business users, but belong to the general population. And the technology is becoming increasingly mobile. Existing usability methods and tools are suitable for testing stationary in-office ICT, but do not cover the necessary span of mobile ICT use. Opposed to traditional desktop computation, mobile ICT involves issues like use in multiple contexts, multiple users, and continuous everyday use [Abowd & Mynatt (2000)]. Traditional usability work typically concerns single users using one single technology to solve well-defined tasks in an undisturbed environment. Solving tasks in this manner requires different strategies, other sources of support, and is accompanied by problems other than the solving of tasks in complex and shifting environments [Zsambok (1997)]. The traditional usability framework needs to be supplemented by methods tailored to gain knowledge of user problems in the ‘real world’, actual user contexts, and users’ integration of mobile ICT in their everyday lives. Mobile computing systems typically have short product realisation cycles. Consequently, cost and time efficient methods and tools for usability analysis and evaluation are required (Millen, 2000). What is needed are ‘quick and clean’ (as opposed to ‘quick and dirty’) methods of usability analysis and evaluation [Wichansky (2000)]. One direction with potential that has been identified is that of training users to report their own critical incidents [Castillo, Hartson, & Hix (1998); Palen (2000)]. In response to these challenges, some early work on the development of methods particularly tailored for mobile usability analysis and evaluation has been initiated. The focus of attention has been on users performing real tasks in their normal environment, and the methods include: • Angry Face. User-initiated usability evaluation by way of an Angry Face button. • User Context Logging. Selected users’ reporting their contexts of use ‘on the fly’.