Leo Study Unstable Asthma

Inclusion Criteria: * Children aged ≥2 years old and \<18 years old at time of consent * Children with a legal guardian able to sign consent for study participation * Children and caregivers able to read and understand English or Spanish * Children who are currently hospitalized with acute exacerbation of asthma * Child's caregiver is able to communicate using SMS * Child has an asthma inhaler Exclusion Criteria: * Children with complex medical conditions which may hinder their ability to complete protocol assessments * Children with an active skin condition involving the area on the chest wall where the Leo device will be attached. E.g. inflamed and/or infected eczema or other skin conditions involving the anterior chest wall at the time of recruitment * Children with any implanted medical devices, E.g. cardiac pacemaker * Children with any history of known allergic reaction to adhesives or hydrogels, as the ones used with the Leo device