How does ios9 set the ringtone?

You can download ringtones with the help of synchronization assistant, which is simple and easy to use.

The specific operation is as follows:

1) download an MP3 format;

2) download and install the synchronization assistant on the computer;

3) Open the Synchronization Assistant and select "More Features" at the top. There are ringtones in common tools;

4) After entering, select the previously downloaded music, set the ringtone length according to personal preference, and then save the ringtone and convert it into M4R format;

5) Finally, import the Apple mobile phone and set it as a ringtone.