Background The field of digital technologies being developed or applied to support nursing care is very extensive. The aim of this scoping review is to provide an overview on technologies for which results on positive or negative effects on persons in need of care, caregivers or care institutions are available – and to appraise the reliability of these results. An additional focus is put on the question which care settings and target groups have been addressed by the research so far. Methods A scoping review design has been used to identify studies focussing on the effectiveness of digital technologies in nursing care for persons in need of care, caregivers or care institutions. The screening process included 19.510 scientific publications from 9 databases. Results A total of 123 single studies and 31 reviews were subjected to the analysis. The range of technologies that is researched to support nursing care is wide. The included technologies comprise nursing and health information technologies, such as assistive devices, information and communication technologies (including decision support systems, electronic health records, hospital and nursing home information systems), sensors and robotic technologies. The results show that there are many studies that demonstrate positive effects of the technologies, but the level of evidence is mostly low and study sizes are often small. Hardly any technology has been researched intensively enough to produce conclusive results. Studies on a high level of evidence (RCTs) lack for nearly all technological areas. Heterogeneous results in some areas indicate that effects may depend strongly on the mode and and specific context into which the technologies are introduced. Most studies are situated in inpatient care settings. Conclusion Due to the limited evidence on effectiveness of digital technologies in nursing care, it is not surprising that care institutions are reluctant to put innovative technologies into practice. The scoping review indicates technology areas that should be subject to future research with higher quality studies. Research on outpatient care settings, informal care arrangements and cross-sectoral care should be intensified to further exploit the potential of digital technologies to improve independence of care-recipients and unburden formal an informal carers.