Monstas are interactive exercise toys for children with juvenile arthritis, a joint disease most common in the hands. Juvenile arthritis has no cure, but it can be taken into remission through constant exercise. But patients often find exercise is painful and see it as a chore—worsening the arthritis. Monstas helps children heal by teaching them how to exercise correctly using a game on the iPad® with exercise tools that are friendly and soft. Monstas consists of three tools targeting a different joint group of the hand: wrist, knuckles and mid-finger joints. Each tool is squeezed on top of the iPad to create different game movements. The tablet is able to recognize the tool through simple conduction and indicate that the exercise was achieved. Children play while getting healthier.