Background: The global acceptance and use of technology in health care has resulted in an abundance of mobile health (mHealth) applications (apps) available for use in the delivery and improvement of care. With so many apps available to patients and clinicians, it is important to understand how data from apps are being used to inform quality improvement in practice. Aim: The aim of this integrative review is to establish current knowledge of how mHealth apps are used to produce data to inform quality improvement in health care. Methods: Scopus, Web of Science, CINAHL, and Medline Plus Full Text databases were searched for peer-reviewed papers written in English. The inclusion criteria comprised of full-text, empirical research studies relating to mobile health application use (not development) in clinical care. Results: Nineteen studies met inclusion criteria. The functions of the apps outlined in the studies can be summarized into four different categories: communication, illness management, clinical management, and education/information. The types of data collected by the apps included numerical, textual, photographic, and graphical with several apps able to collect a variety of data types. Analysis of the studies showed that although data collection is rarely outlined as the explicit purpose of mHealth apps, data collected through such technology are and can be used to inform practice change both in real time and retrospectively. Linking Evidence to Action: This review highlights while this is an emerging area, data obtained from mHealth apps can and are being used to inform quality improvement in health care. Further research is required in this area to adequately understand how data from mHealth apps can be used to produce quality improvement, specifically in relation to nursing. This review also highlights a need for the development of apps that aim to capture data to inform quality improvement, particularly from the patient perspective.