Physicians currently have no objective information about the intensity and quality of a Stroke patient's daily-life activities after returning home from the rehabilitation hospital. Therefore there is a need to unobtrusively monitor patients performing daily life tasks at home. Within the INTERACTION project, a new inertial based sensor suit was developed, which is able to measure Stroke patients at home. This research extend the INTERACTION project by developing an Arm Usage Coach (AUC), which stimulates the patients affected arm to be used more often at home. The results of a usability evaluation showed high scores in usability, but some design and wear ability problems were found. An open loop evaluation of Stroke patient data showed how different decision criteria parameters, for applying feedback to the patient, resulted in different outcomes of feedback given. Based on both evaluation results, a new prototype is in development, which will be evaluated by Stroke patients in clinic.