Contacts on Android are highly personalized. You can assign and add ringtone, message alert tone to a contact on Samsung Galaxy S4, S3. choose from music player or the default ringtones and alerts by following these steps:
To assign a ringtone to a contact:
1. Open "Contact" App
2. Tap on the name of the contact to add ringtone
3. Find "Ringtone" and tap on the "Default"
4. A list of ringtones is shown. You can either select between them or hit "Add" button to add from your music library
Note that depending on your installed music players and apps, you may have different options when hitting the "Add" button. Open one of your music players and select your music track.
5. Hit on "Save" button and you are done
To assign a message alert to a contact:
1. Open "Contact" App
2. Tap on the name of the contact to add message alert
3. Find "Message Alert" and tap on the "Default"
4. A list of ringtones is shown.
5. Select from the list and "Save" the process
Read More Galaxy S4 Tips and Tricks