Inclusion Criteria:  Being enrolled in Oxford clinics Owning or having access to a smartphone with either Android or iOS Being able to use a smartphone app Being able to walk  Exclusion Criteria:  Long term oxygen therapy Cognitive impairments Cannot use a smartphone Pregnancy Not able to complete a 6MWT Any other significant disease or disorder which, in the opinion of the Investigator, may either put the participants at risk because of participation in the trial, or may influence the result of the trial, or the participant's ability to participate in the trial.