You can choose a unique ringtone for calls from specific people so that you'll know instantly who's calling. All other calls use the default ringtone.
Adjust the settings:
Touch Phone ringtone and select a ringtone or select None if you don't want the phone to ring.
Contact-specific ringtones apply only to phone calls, not to notifications of text or email messages from that person.
To change the default sound used for notifications:
You can also assign a specific sound to notifications from some apps. Open the app, touch
or
and look for Settings.
Although your phone comes with lots of ringtones, you can also download custom sounds.
To download ringtones using an app:
If you downloaded a ringtone (.mp3) to your phone without using a ringtone app:
Update your settings to select the new ringtone.