By January 2020, German patients will be able to forward the cost of doctor prescribed health apps to their health insurance company.
Not all apps are covered, for apps to be covered by health insurance they need to be approved by the Federal Institute for Drugs and Medical Devices (Bfarm). Bfarm will test apps for data security, privacy, and functionality. After the approval, the app manufacturer has one year to demonstrate that their app improves treatment to qualify for insurance coverage.
How much a manufacturer can charge will be negotiated between the manufacturer and GFK-Spitzenverband (appointed association).
Also, the news magazine Spiegel.de wrote an article about this topic; you can read this article in German here: https://www.spiegel.de/gesundheit/diagnose/gesetzentwurf-gesundheits-apps-auf-rezept-a-1276653.html