Recent mobile applications empower citizens to monitor noise pollution or report on
features of their urban environment. One important aspect of urban life has, however,
not been sufficiently addressed, namely the safety of citizens. We present a privacyaware
application called uSafe, in which users indicate how safe they feel in geographical
locations. These feelings are then consolidated into summary maps accessible by other
users and urban planners. We evaluate our concept with a questionnaire-based study
involving 183 participants. The results confirm the utility of uSafe and show that privacy
protection is a decisive factor in their decision to contribute to it.