Cough Management Wellness App for Refractory or Unexplained Chronic Cough

Inclusion Criteria: * Age 21 or older. * Currently suffering from a cough that started at least 8 weeks ago that is largely unproductive (i.e., at least 50% of the time the cough produces zero mucus that needs to be spit out or swallowed). * Normal chest X-ray or chest CT scan at some point that was prescribed specifically for their cough. * At least one physician visit for cough with standard-of-care therapy but inadequate symptom relief. * Stability of treatment: willing to avoid new cough treatments during study or report changes if they occur. * Ability to comply: willing/able to wear the watch daily for the required duration of study and to complete all required questionnaires. * Informed consent: understanding of the study procedures and agreement to comply with protocol. Exclusion Criteria: * Recent upper respiratory infection (past 4 weeks). * History of hemoptysis (coughing up blood) since onset of the current cough. * Current smoker (incl. vaping) of any substance. * ≥10 consecutive pack-years smoking history within \<10 years prior to screening. * Diagnosed with a chronic lung condition (COPD, emphysema, lung cancer, IPF, chronic bronchitis, asthma). Note: Suspected asthma without confirmed diagnosis or benefit from asthma therapy is not an exclusion. * Current or past head/neck cancer. * Difficulty swallowing. * On ACE inhibitors, such as Benzapril (Lotensin), Captopril (Capoten), Enalapril/Enalaprilat (Vasotec oral and injectable), Fosinopril (Monopril), Lisin…