98 Personal Content Experience: Managing Digital Life in the Mobile Age company where the user works, it cannot be sent to e-mail addresses 25 that do not belong to the same organization. Further metadata may contain information, such as legal conditions and copyrights, which affect how to use that data. 4.5.6 Constructing Views The metadata plays an important role in constructing UI views to objects. For instance, it can help in selecting what objects are to be displayed, how they are organized, and what information per object is presented. In addition, metadata can be used for generating the UI layout. For example, Context Comic (Aaltonen et al. 2005) diary application uses metadata for selecting the personal content objects that belong to the diary and forming groups of objects based on diary events. For each event, the event’s importance is derived from metadata attributes of its objects (such as number of times that the object has been opened or sent) and the same information is used for selecting the object that visualizes the event. The application further scales images and places them on a grid on the basis of the event’s importance. 4.5.7 Better Recommendations Metadata could also fi ne-tune the recommendation systems by taking into account context and comments by others people who have similar preferences. For instance, in a movie recommendation service, you might favour ratings from people who have seen the same movies you liked. Metadata could also link the recommendations to the individuals who contributed them so that their digital reputation could affect the ranking. 4.5.8 Reusing / Remixing / Reconstructing Digital content readily lends itself to reuse, if the copyrights allow. Thanks to this, more and more of contemporary content are collages. Consider a typical music video on Music TV. Often the music track is created using dozens of sound samples obtained from commercial sound libraries, and the same may apply to the video fi les and visual effects. The metadata in these fi les may retain references to the original 25 Which may not be quite what you want if, for instance, you are sending some promotion material to your customers. Unfortunately, simple constraints like this will often fail with the complex situations found in everyday life.