Adaptive personalization, where the system adapts the interface to a user's needs, has the potential for significant performance benefits on small screen devices. However, research on adaptive interfaces has almost exclusively focused on desktop displays. To explore how well previous findings generalize to small screen devices, we conducted a study with 36 subjects to compare adaptive interfaces for small and desktop-sized screens. Results show that high accuracy adaptive menus have an even larger positive impact on performance and satisfaction when screen real estate is constrained. The drawback of the high accuracy menus, however, is that they reduce the user's awareness of the full set of items in the interface, potentially making it more difficult for users to learn about new features. Author Keywords Adaptive interfaces, personalization, small screen devices, menu design, user study, interaction techniques. ACM Classification Keywords H.5.2 [User Interfaces]: Evaluation...