Group 2 (IWT with without motivational support after 8-14 weeks): Patients in this group will be engaged to IWT with the IW app (see: The InterWalk Application). The intervention period will follow the period in which the rehabilitation program is carried out in the municipality (duration from 8-14 weeks). The patients are encouraged to perform IWT three times per week, 60 minutes per session. The municipality offers to walk with the patient´s two times per week for 60 minutes per session in group sessions with additional 30 minutes of group discussion afterwards. The last and third time the patients have to walk by themselves for 60 minutes per session. The participating patients will receive a thorough introduction to the IW app and follow-up during the intervention (8-14 weeks) from the health professionals. At the end of the intervention period, the health professionals, conducts a transition program, preparing the patients to continue IWT with IW app on their own. There will be no follow-up from the municipality, which is the normal procedure in the municipality.