First install HR Monitor on your Gear S2 or S3 smartwatch. You can find HR Monitor in the Gear app store. Then install HR Monitor on your phone. The phone app and the Gear app work closely together. You cannot use HR Monitor to monitor your heart rate and at the same time use S Health to monitor your heart rate. HR Monitor will not work well when the S Health app on your Gear S2 or S3 uses the heart rate sensor.
You can use HR Monitor for free during one week. After that, you have to pay for this app once. The app will let you know how to pay. Purchasing is done in this way to give you the opportunity to test the app before purchasing.
When you uninstall the phone app, also uninstall the Gear app. Else the phone will notify you that the phone app is missing.
You can use HR Monitor stand alone, without Gear device, if you only want to synchronize heart rate and steps from S Health to Google Fit.
