Purpose: An alarming two thirds of adults aged 50 years or over with hearing impairment who could benefit from hearing aids do not own any, leaving these adults with no support to self-manage their hearing problems. In the HEAR-aware project, it is hypothesized that self-management can be facilitated via a smartphone app if its educational content is tailored to a person’s dynamic stage of readiness to take action on their hearing (stage of change) and to a person’s dynamic acoustical situations (as measured via a wearable microphone) and associated challenges (as captured via ecological momentary assessment). As such, the HEAR-aware app would be an ecological momentary intervention. This research note describes the rationale and theoretical underpinnings of the app, as well as the rationale for planning a series of studies to develop and evaluate it. Study Designs: After a preparatory phase, Study 1 includes qualitative group interviews to assess user needs. Next, a creative session will be held, in which all stakeholders involved will work toward a specified version of the app. Subsequently, prototypes of the app will be developed and pilot-tested (Pilot Studies 2A and 2B). Users’ usage and ratings (usability and quality indicators) of the app’s elements will be examined and processed in the app. Lastly, the effectiveness of the app’s final version will be examined in a randomized controlled trial (Study 3). Discussion: The project’s merits and challenges will be discussed.