Table 1.

Data extracted from the included studies.

Study information	Data extracted
General study information	Title of publication, year of publication, authors, and journal of publication
Study characteristics	Study design, country of study, analyzed sample size, key inclusion/exclusion criteria, and study arms
Intervention characteristics	App name, device on which the app could be or was utilized, compatible platforms, intended user, aim of the app, vaccines covered by the app, and vaccine-related features of the app
Evaluation	Number of users, impact on the uptake of vaccinations, impact on knowledge/learning, impact on vaccination decision making, perceived credibility, usability/user experiences, popular features, costs/cost-effectiveness, adverse events, and conclusions