ArthCoach is a personal and interactive application made available by Sanofi. The application is a tool that will help you control the evolution of pain caused by osteoarthritis of the knee (OAK). The application allows you to: 1. Access to OAK information, control of the disease and measures to help improve quality of life. 2. Register your knee pain and control the evolution over time. 3. Find examples of physical exercises designed to OAK. 4. Send reports of recorded data to your doctor or healthcare professional in attendance via email from your mobile device. 5. Set alerts and receive reminders of upcoming visits you have with your doctor or health care professional.