A systematic review of recent smartphone, Internet and Web 2.0 interventions to address the HIV continuum of care.

eHealth, mHealth and "Web 2.0" social media strategies can effectively reach and engage key populations in HIV prevention across the testing, treatment, and care continuum. To assess how these tools are currently being used within the field of HIV prevention and care, we systematically reviewed recent (2013-2014) published literature, conference abstracts, and funded research. Our searches identified 23 published intervention studies and 32 funded projects underway. In this synthesis we describe the technology modes applied and the stages of the HIV care cascade addressed, including both primary and secondary prevention activities. Overall trends include use of new tools including social networking sites, provision of real-time assessment and feedback, gamification and virtual reality. While there has been increasing attention to use of technology to address the care continuum, gaps remain around linkage to care, retention in care, and initiation of antiretroviral therapy.