The microwave oven has obviously been a very successful domestic appliance in terms of its diffusion in the western world. Development of the microwave and its entry to the domestic culture has been researched by Cockburn and Ormrod ( 1996): in one phase, the new innovation exploiting fuzzy logic was created to offer the automatic, programmable microwave oven. This innovation was to enable people to cook different kinds of meals by letting the microwave estimate the required cooking time and power.
Despite the early success of the microwave, it has turned out that many of its advanced features are neglected: people mainly use it just for heating and defrosting, not for advanced cooking. Thus, there is a conflict with the existing usage patterns in the real context of use (kitchen, family home and traditions) and the offered (technological) innovation: the microwave user -- especially the advanced cook -- would not be able to make use of the existing knowledge and skills any more and would have to adjust his or her actions to fit the offered technology. However, innovations may be more acceptable for people who are not aware of traditions, conventions and social pressure related to the matter. In the case of the microwave this may mean for example young people -- they may not have to abandon existing skills and practices (i.e. if they have not yet acquired such "kitchen skills").
Despite the failures of microwave oven in certain aspects, it has been a success in terms of rather a limited set of features: heating and defrosting. It fits the modern lifestyle: mothers working outside home can still -- when wanted -- quickly prepare meals for the family. Today's families are busy in their hobbies and other activities so that common meals are becoming rare during the weekdays, also, special diets are increasingly popular. Therefore, it is convenient that everybody can heat their own food in their own time. In general, saving time is important and the microwave supports it in the modern family.
To involve end-users early enough in the design process has become necessary in current product development. There are several participatory design methodologies that can be exploited in early design phases of mobile communication devices ( Schuler and Namioka 1993). At Nokia, Contextual Inquiry (CI) ( Beyer and Holtzblatt 1998) has proved to be one of the most promising approaches among the ethnographical and sociological research methodologies ( Lewis and al. 1996) in researching the context of use ( Väänänen-Vainio-Mattila and Ruuska 1998). CI provides a structured and manageable way -- also in mobile situations -- for gathering insight of users' or