Inclusion Criteria:  Children aged ≥3 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 Investigator confirmation for diagnosis of clinically stable respiratory condition, such as clinically diagnosed asthma Children who are able to follow instructions and complete oscillometry and tidal breathing tasks  Exclusion Criteria:  - Children <3 and >18 years of age Adults (age ≥ 18 years) Children with complex medical conditions which may hinder their ability to complete protocol assessments Children who do not have a legal guardian to sign informed consent form 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 Child is determined not eligible by the assessment of the PI Fever within the 4 weeks prior to enrollment 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 Children who have taken a bronchodilator in the last 12 hours prior to study visit.