How can I get a silent ringtone on my iPhone?
One way to filter out unwanted calls is to assign a silent ringtone to specific contacts. Alternatively, you can assign a silent ringtone as the default ringtone and use normal ringtones for only contacts you want to hear.
The iPhone doesn't come with a silent ringtone. Here's how to add one:
2. Open iTunes. Under LIBRARY on the left-hand menu in iTunes click Ringtones.
3. Copy the silent ringtone into Ringtones.
4. Connect your iPhone to the computer and sync. The silent ringtone will now appear in your list of ringtones and you can assign this ringtone to specific contacts.