The study assesses and describes the interplay between public PC-based Internet access and private mobile-based access for urban teenaged public access venue (PAV) users in Cape Town. South Africa is a particularly fruitful “leading edge” environment to do this work since not only mobile use, but specifically mobile Internet use, is increasingly common even among resource-constrained young people. We combine quantitative surveys with open-ended interviews of users and PAV operators. Discussion is structured around five claims: 1) Public access and private mobiles offer different affordances, and teenage users have developed complex, fine-grained practices which help them to negotiate the respective strengths and weaknesses of the affordances. 2) The PAV provides non-substitutable impact to resource-constrained users, even those with “the Internet in their pocket.” 3) Public access supports the development of digital literacies associated with hyperlinked media and large-format documents, while mobile access supports everyday social literacies and messaging. 4) Teens can use a combination of mobile and public access Internet resources to participate in networked media production and grassroots economic mobilization. 5) PAV operators can improve venue rules and skills to encourage the complementary use of the mobile Internet.