Background: ST-segment elevation myocardial infarction (STEMI) is a high-risk patient medical emergency. We developed a secure mobile application, STEMIcathAID, to optimize care for STEMI patients by providing a digital platform for communication between the STEMI care team members, EKG transmission, cardiac catherization laboratory (cath lab) activation and ambulance tracking. The aim of this report is to describe the implementation of the app into the current STEMI workflow in preparation for a pilot project employing the app for inter-hospital STEMI transfer. Approach: App deployment involved key leadership stakeholders from all multidisciplinary teams taking care of STEMI patients. The team developed a transition plan addressing all aspects of the health system improvement process including the workflow analysis and redesign, app installation, personnel training including user account access to the app, and development of a quality assurance program for progress evaluation. The pilot will go live in the Emergency Department (ED) of one of the hospitals within the Mount Sinai Hospital System (MSHS) during the daytime weekday hours at the beginning and extending to 24/7 schedule over 4-6 weeks. For the duration of the pilot, ED personnel will combine the STEMIcathAID app activation with previous established STEMI activation processes through the MSHS Clinical Command Center (CCC) to ensure efficient and reliable response to a STEMI alert. More than 250 people were provisioned app accounts including ED Physicians and frontline nurses, and trained on their user-specific roles and responsibilities and scheduled in the app. The team will be provided with a feedback form that is discipline specific to complete after every STEMI case in order to collect information on user experience with the STEMIcathAID app functionality. The form will also provide quantitative metrics for the key time sensitive steps in STEMI care. Conclusions: We developed a uniform approach for deployment of a mobile application for STEMI activation and transfer in a large urban healthcare system to optimize the clinical workflow in STEMI care. The results of the pilot will demonstrate whether the app has a significant impact on the quality of care for transfer of STEMI patients.