To start with answering a question, how to change Yahoo password on iPhone iOS 11, the first step you must log in to your Yahoo app. Doing so will let you know the menu section where you can find the Manage Accounts option. Then move towards the Account info > Security settings > Change password. By tapping on the Change password, you will be needed to enter a new password twice in order to confirm your password to be correct. This is it! 

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