Since there are several apps for the certain actions or tasks, no wonder you want to assign specific apps for specific actions. To setup and change default apps on Galaxy S7 and Galaxy S7 Edge, do as follows:
1. Open the Settings application on your Samsung device
2. Scroll down to the Phone settings and go to the Applications settings
3. Touch the Default Applications option to customize and specify which apps should open which tasks or actions
4. Here, by default you get to change the Default Browsing App, Calling Apps, Messaging App and the Home screen launcher.
5. To change the default app for each action, simply touch it and then select a new default app for that specific task/action.
If you want to change the default apps for other tasks on your Galaxy S7 or Galaxy S7 Edge, you need to do as follows:
1. Say, Google Play Music is your default music player app on your S7 and you want to change it to a new app you have just installed (we call it Music Player app)
2. Go to the Settings > Applications and tap to open the Google Play Music app from the list
3. Tap the Open by Default option, and touch the Clear Defaults button to reset app preference for playing music
4. Now, go back to your File Manager and start playing a new file. As you touch to open the music file, you are asked to specify a default app for this action.
5. Select the Music Player app and make sure to set it as the Default music player and not just Once.