If you don't have AssistiveTouch enabled, you'll need to enable it first.
 In order to change your call volume, you'll need to be in a call first.


To initiate a call, open the Phone app, select a contact from the "Contacts" tab, and tap Call.
To receive a call, tap Accept (or slide the Swipe to Answer button to the right if your phone is locked).
 You may want to use your iPhone's speakerphone while doing this.
, Doing so will change your call volume accordingly.
Make sure AssistiveTouch is enabled.
Initiate or receive a call.
Tap the AssistiveTouch square.
Tap Device.

,
Tap Volume Up or Volume Down.
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