BackgroundPostpartum depression is a major public health concern, which is associated with negative consequences for both mothers and children. Unfortunately, many affected women neither understand the warning signs of postpartum depression nor do they know where to seek help. The aim of this study was to evaluate the feasibility of SmartMoms, a German mobile web application (web app) designed to inform women about postpartum depression, support them, and provide an easily accessible self-screening instrument.MethodsAfter its development, SmartMoms was distributed through healthcare providers and social media. Feasibility was assessed by examining (1) the experience of postpartum women with the web app, (2) user behaviour, and (3) the experience of healthcare providers with the web app and its distribution. A mixed methods approach was used, including online surveys, usage data, and interviews.ResultsMost women used SmartMoms to prevent postpartum depression and rated the web app as good (on average 4.36 out of 5 stars). The majority of women (62.2%) accessing the self-screening instrument showed a risk for postpartum depression (Edinburgh Postnatal Depression scale score≥12). Most providers (n = 12/13) felt supported through SmartMoms in discussing postpartum depression and considered it a useful offer. Suggestions for improvement were provided.ConclusionsSmartMoms meets the needs and expectations of mothers and healthcare providers interested in postpartum depression but should be further adapted to include more specific support options and additional information for professionals.Supplementary InformationThe online version contains supplementary material available at 10.1186/s12884-023-05680-9.