Sitting while wearing the iWALK is possible. However, you need ample space in front of your chair for the lower crutch below your knee to extend. You will need to remove the iWALK completely when sitting in a car or using the restroom. However, the iWALK was designed to put on and take off easily and after just a little bit of practice, most people can take the iWALK on and off in under 15 seconds.
Here is a quick video showing two options on how to sit down and stand up using the iWALK Crutch.