What is the effect of mobile phone ownership on civic and political engagement? With the spread of low-cost hand-held phones to all corners of the globe, the impact of the mobile technology revolution on politics is of great importance. Existing observational studies generally find a positive association between mobile communication and civic and political participation, including on violent and non-violent mobilization. Experimental evidence has been lacking on this question, however. We fill this gap in one of the first experimental studies on the impact of mobile phone ownership on civic engagement. Leveraging an existing randomized-controlled trial among 2,000 women in Tanzania that randomly assigned basic phone and smartphones to non-phone owners in Tanzania, we analyze the impact of owning a phone for one year versus not having had a phone on participation in a land rights workshop—a salient public policy issue in Tanzania. Our study offers new insights into how mobile technology affects individual efficacy and how one receives information about and acts on civic engagement opportunities.