Creating user friendly map interfaces for the mobile platform presents several challenges that are uniquely different from those of their desktop counterparts. High resolution, photo realistic maps can now be displayed on mobile phones. While these graphics are visually pleasing, they do impact the user’s cognitive load. Further, small displays and limited interaction capabilities often make mobile map-based systems difficult to design and frustrating to use. In this paper, we discuss lessons learnt from designing and implementing mobile map interfaces through two examples: tourist maps and traffic maps. In particular, we discuss the rendering, user interaction, and system adaptations required for these mobile map interfaces. Categories and Subject Descriptors H.5.1 [Information Interfaces and Presentation]: Multimedia Information SystemsMaps; H.5.2 [Information Interfaces and Presentation]: User Interfaces General Terms Design, Human Factors Keywords maps, mobile, design, interact...