Chapter 6: User Interfaces for Mobile Media 279 tailored to their purposes. Due to this and exploiting the concept of application, multi-tasking and task switching is almost as important as with desktop computers. Toolbox devices usually provide platforms (such as Series 60, UIQ, or Linux) for third-party application developers. These devices typically provide comprehensive UI style guides, examples, and other docu- mentation that aid in using the platform’s UI components and conven- tions for UI design and implementation. In addition, toolbox devices are appealing targets for developers as they provide them with services, such as messaging and imaging. They also have more processing power and memory, better graphics and audio capabilities, and various con- nectivity features (such as, GSM, 3G, WLAN, and Bluetooth). 6.7 Summary The user interface is a channel for the user to communicate their actions to the system and receive feedback when performing a task, that is, there is no other way to interact with the product. Therefore, in whatever way the UI fails in some aspect, it will have a negative impact on the product, which eventually reduces the use of the product and, ultimately, sales. To create successful products, designers should know who the design is being created for, why it is done, and what is the best way to do it with the given technology? Realizing these goals requires a lot of work, including research on markets, trends, technologies, and competitors to check feasibility on several levels. Getting the basics right is only the fi rst step towards a successful UI, the next one is to defi ne the product’s users and tasks. There are many options available for this task, but most likely it will succeed with the aid of user-centred design methods . . . and with common sense. The user interface design involves dividing the tasks between the views, defi ning the structure and the UI components in a manner that follows all general UI design principles, platform guidelines and conventions, and is aesthetically pleasing to all the senses. It is highly unlikely that any design is initially perfect. It must be validated and iterated with various usability engineering methods. Moreover, a triumphant UI design requires deep understanding of the technologies and how to use them in the best possible way. Because mobile computing and mobile personal content are still in their infancy, there is plenty of room for introducing new and novel solutions. They can relate to the perceivable part of the UI (presenta- tion techniques), to the system core (automation and adaptation