In this paper we report on a participatory design study with young girls. Our goal was to create a mobile phone app to display the spatial proximity of friends in an abstract and privacy-aware manner. A group of 16 girls worked along the user-centred design process to create initial paper-based designs of an app that respects one's friends privacy while displaying their proximity to allow for spontaneous meetings or re-grouping after separation. Our participants created very promising results which we intend to implement and evaluate further against a broader audience.