Despite major advancements in mechanical circulatory support, the self-management (SM) for patients with a left-ventricular assist device (LVAD) remains complex and challenging for patients and their caregivers. We have developed a mobile phone application (VAD Care App) to organize and simplify the LVAD SM process. This article describes the development and feasibility study of the app as an SM tool for LVAD patients and caregivers requiring support from ventricular assist device (VAD) coordinators. The specific aim was to evaluate the app's acceptability and usability and the users' competency. App features included an automated alert, data collection/reporting, and dynamic real-time interaction systems embedded in the LVAD SM process. Beta-testing of the prototype was completed by five adults. For the feasibility study, we employed a mixed-method descriptive research design involving nine patients and nine caregivers from two VAD centers in the Midwest. We asked them to use the app daily for more than 30 days and complete an app Evaluation Questionnaire and an interview. The questionnaire uses a five-point rating scale (1 = strongly disagree to 5 = strongly agree) evaluating usability, acceptability, and competency domains. Data generated from the questionnaires and interviews were analyzed with descriptive statistics and content analytic procedures. A total of 16 users (eight patients [all male] and eight caregivers [seven female]) aged 22 to 68 years completed the 30 day study. Median acceptability, usability, and competency scores were 4.6, 4.5, and 4.7, respectively. Based on the data, it is feasible for patients and caregivers to use an app as an LVAD SM tool warranting further research.