The Developer options on the Samsung Galaxy S7 are not enabled by factory in Android marshmallow, which means that you must activate this option first to use it. If you do not know how to activate the developer mode on the Samsung Galaxy S7, then we would like to explain that more precisely here:
From the home screen of the Samsung Galaxy S7 navigate to:
Menu --> Settings --> device information
In this Android Marshmallow submenu you can now see various information about your Samsung Galaxy S7. In order to enable the developer options, tap several times in rapid succession on the "build number" entry.
After about the seventh time tap, a message appears with "developer options enabled".
The just unlocked developer options can now be found in the settings section of your Samsung Galaxy S7. This new entry can now be opened and activated via the controller. You have now learned how you can activate on the new Samsung Galaxy S7 the Android Marshmallow developer options.