Medical data generated by wearables and smartphones can add value to health care and medical research. This also applies to the ECG data that is created with Apple Watch 4 or later. However, Apple currently does not provide an efficient solution for accessing and sharing ECG raw data in a standardized data format. Our method aims to provide a solution that enables patients to share their Apple Watch's ECG data with any health care institution via an iPhone application. We achieved this by implementing a parser in Swift that converts the Apple Watch's raw ECG data into a FHIR observation. Furthermore, we added the capability of transmitting these observations to a specified server and equipping it with the patient's reference number. The result is a user-friendly iPhone application, enabling patients to share their Apple Watch's ECG data in a widely known health data standard with minimal effort. This allows the personnel involved in the patient's treatment to use data that was previously difficult to access for further analyses and processing. Our solution can facilitate research for new treatment methods, for example, utilizing the Apple Watch for continuous monitoring of heart activity and early detection of heart conditions.
Keywords: ECG data; FHIR; Interoperability; Smart Watch.