While co-located social media previously has been employed to enhance interaction in community building activities in previous work, its range of e.ects have not been quantitatively described. In this study, we introduce a co-located social media app called Speak Up to a community building project in the Za'atari Syrian refugee camp in Jordan. To overcome issues such as the lack of Internet access, we purposefully adapted the design of the application and ported its server to a low cost single board computer on a Raspberry Pi. We explore the effects of Speak Up through field experiments with one control and two treatment groups, as well as with interviews and observations. Our results show that Speak Up significantly increases refugees' level of participation and sense of community. Importantly, with the use of the application, female and male participants demonstrate no significant differences in participation, showing that the use of such applications can be equalizing. We also found that co-located social media supports asynchronous interaction when outside-The-classroom activities are involved.