With the advent of mobile computing and mobile services becoming more widespread and more complex, the development process of those services requires an ever more important focus on numerous design issues. The heterogeneous environment, reaching from different networks and devices to different software platforms embedded on such devices, implies difficulties in making a mobile service broadly available. Another interesting aspects is, that mobility and personalization enable the creation of location based services which may be coupled with the user’s context additionally. Thus, this circumstances require, that a mobile service provide an adequate location- and context-awareness. This paper enumerates some fundamental aspects of mobile service design summarized from current research results. At this, we focus on the aspects of heterogeneity and location/context-awareness. Beginning with regarding the mobile services’ environment, we consider the requirements of a mobile service and...