Heart Monitor. Heartbeat funktioniert nicht

Simple operation: with your fingers on the back of the camera and flashlight, gently press, you can read the pulse in a few seconds.  Keep track of your pulse measurements with the app in a very easy way with a simple tap of a button!  You can save your heart rate in a different state (such as exercise, rest, etc.  Just open the app, you can measure your heart rate anytime and anywhere.  Subscription period- 1 year.  Every 1 year your subscription renews.  Any unused portion of a free trial period, if offered, will be forfeited when the user purchases a subscription to that publication.