iPhone allows users to customize their ringtones. For example, you can set specific iPhone ringtones for specific person or a group of contacts, such as friends, colleagues, relatives, or any other groups you set up on your iPhone.
How to Activate Ringtones on iPhone?
Step 1: Go to the home screen of your iPhone. Tap to start Settings app.

Step 2: Tap Sounds from the left menu, then tap Ringtone button. You will get a list of all ringtones on your iPhone. Tap to set the ringtones for your iPhone.
How to set up Ringtones for specific contact on iPhone?
To customize ringtones for specific persons, open Contacts, choose a person, tap on Edit button, press on Ringtone and select your target one.
Make iPhone ringtones
Want to create your own ringtones? You can record sounds and convert them into iPhone ringtone with iTunes. See this step-by-step guide to make free ringtones for iPhone. You can also convert music files such as MP3 songs to iPhone ringtones with iTunes.
I just purchased a ringtone for my iphone6+ and have it assigned it to a specific caller however it has not activated. Have I missed a step?
run the Contacts app, find and open the Caller or contact person to view its details, can you see the new ringtone listed under Ringtone? If so you can tap on it to hear a preview. If you can’t hear anything try a different ringtone see if any update.
FYI, to assign custom ringtone to contacts on iPhone, firstly open Contacts app, find and tap to open the contact details, tap the Edit button in the top right corner, you can then find and edit ringtone for this specific person or caller.
I have an iphone6s and have had a recent update 9.0.3 I think it was, the phone is permanently on silent ring as I like to keep the keypad locked when not in use. I don’t want to unlock it permanently as its a deterrent to stop people messing with it but I do want to be notified of calls coming in by a ringtone whilst it’s locked Help
your should hear the ringtone when calls coming in and your phone screen is locked. Is the Ringer button turned on? You can find more tips from my response to @Raymond on December 23, 2015 above.
I have an iPhone 6plus & am having the same problem my phone only vibrates no ring ever where can I find the ringer on button you are talking about
please refer to this page: https://www.softwarert.com/iphone-ringer-mute-switch/.
by the way, can you talk and listen properly when you answer the phone?
I found a tiny button on the left upper corner when you are holding the phone towards you almost looks like where you plug something in. Use your finger nail & just flip that up. I guess they flip that down for shipping! It works now!!
thanks for the feedback. i think you are referring to the mute and ringer switch or toggle which is just above the volume up/down buttons at the left side of the iPhone.