Vaccine information of varying quality is available through many different sources. We describe the creation, release and utilization of ReadyVax, a new mobile smartphone app providing access to trustworthy, evidence-based vaccine information for a target audience of healthcare providers, pharmacists, and patients (including parents of children). We describe the information content and technical development of ReadyVax. Between the hard launch of the app on February 12, 2015 and October 8, 2016, the app has been downloaded by 5,142 unique users, with 6,841 total app sessions initiated, comprising a total of 15,491 screen views (2.3 screens/session on average). ReadyVax has been downloaded by users in 102 different countries; most users (52%) are from the United States. We are continuing outreach efforts to increase app use, and planning for development of an Android-compatible version of ReadyVax, to increase the available market for the app.
Keywords: app; smartphone; vaccination; vaccine.