Several research groups have demonstrated advantages of extending a mobile device’s input vocabulary with in-air gestures. Such gestures show promise but are not yet being integrated onto commercial devices. One reason for this might be the uncertainty about users’ perceptions regarding the social acceptance of such around-device gestures. In three studies, performed in public settings, we explore users’ and spectators’ attitudes about using around-device gestures in public. The results show that people are concerned about others’ reactions. They are also sensitive and selective regarding where and in front of whom they would feel comfortable using around-device gestures. However, acceptance and comfort are strongly linked to gesture characteristics, such as, gesture size, duration and in-air position. Based on our findings we present recommendations for around-device input designers and suggest new approaches for evaluating the social acceptability of novel input methods.