The thesis project underlines the importance of designing calm and subtle technologies, by exploring how mobile communicative technologies, such as cell phones, could notify their users about incoming information in a more natural, and non-intrusive manner. The aim of the thesis was to find a way for cell phones to act more appropriately in public and social settings, where they now often are considered intrusive due to their uninhibited manifestations.The thesis provides a theoretical understanding of how normative expectations of cell phone conduct are constituted and maintained within public and social settings. The theories are further grounded in practical work, where the project employ user centered design methods and techniques to, in a collaborative manner, together with users explore the research field to generate insights. Solutions have further been prototyped and evaluated together with users in their everyday settings.Taking inspiration from calm technology, the project looks into how information can be notified, in a more subtle manner in the periphery of the user’s attention. Users’ own priming abilities have been considered as a personal way to recognize the notification and to further associate it as relevant information.As a solution for intrusive cell phones, the thesis proposes Knot; a signature based notification system, which builds on friends’ abilities to recognize each other’s characteristic traits. The system consists of a notification rope, which is a free standing phone accessory that twists and turns, when new information is arriving to the user’s cell phone. It can present whom the information is from by shaping itself into the sender’s representative Knot-signature. If the user can recognize the signature, it will immediately trigger a meaningful association to the person who sent the information.The solution builds upon the restrictiveness between those who can associate a certain signature to a certain person, and those who cannot. For those who have the ability to associate to the signature, its role as a notifier will become meaningful and informative, while for others, who do not share this ability, the signature would be subtle and meaningless, and hence not interfering. The thesis exemplifies how interfaces could provide users with output in a more natural way, by considering users’ previous skills and knowledge, and primarily their priming abilities.