ResAppDx is an innovative mobile application designed to help users identify potential causes of their respiratory symptoms through a simple cough test. Suitable specifically for adults, ResAppDx provides a convenient and non-intrusive method to assess respiratory health. The app requires users to enter a unique code provided by their healthcare provider to access its features. Once activated, ResAppDx prompts users to perform a cough test by coughing a few times near their phone's microphone. The app uses advanced algorithms to analyse the sound of the coughs, aiming to determine potential reasons for feeling unwell. This analysis is then shared directly with the user's doctor, who can review the results and decide if any medical intervention is required. Developed with the expertise of healthcare professionals and grounded in evidence-based research, ResAppDx is specifically tailored to offer individualised respiratory health assessments. The collaboration with medical experts ensures that the diagnostic capabilities of ResAppDx are both reliable and accurate, providing an essential tool for better understanding respiratory conditions. The app is not available for direct purchase or general download. Instead, it is provided free of charge through healthcare providers who issue the necessary access code. This ensures that the usage of ResAppDx is regulated and that medical professionals can efficiently integrate the results into their patient assessments. ResAppDx is not just an app, but a specialised tool designed to offer personalised insights into respiratory health. Its purpose is to help both patients and clinicians by providing a convenient method to conduct preliminary diagnostics. As a result, ResAppDx stands as an essential resource for anyone looking to understand the cause of their respiratory discomfort. In summary, ResAppDx offers a unique, evidence-based approach to diagnosing respiratory issues. It simplifies the initial diagnostic process through a straightforward cough test, making it accessible and user-friendly for adult patients. By facilitating better communication between patients and healthcare providers, ResAppDx enables more comprehensive and personalised treatment plans. The app's development involved close collaboration with healthcare professionals, ensuring that it adheres to the highest standards of clinical accuracy and reliability. ResAppDx is a remarkable advancement in the field of respiratory diagnostics, providing a specialised tool that merges technology with medical expertise for optimised patient care.