We present a novel design of an augmented reality interface to support indoor navigation. We combine activity-based instructions with sparse 3D localisation at selected info points in the building. Based on localisation accuracy and the users’ activities, such as walking or standing still, the interface adapts the visualisation by changing the density and quality of information shown. We refine and validate our design through user involvement in pilot studies. We finally present the results of a comparative study conducted to validate the effectiveness of our design and to explore how the presence of info points affects users’ performance on indoor navigation tasks. The results of this study validate our design and show an improvement in task performance when info points are present, which act as confirmation points and provide an overview of the task.