How to delete all SMS messages on Apple 4s

Step 1: Open the phone settings icon.

Step 2: enter the phone settings, and you will see iCloud when you drop it down. Click it!

Step 3: After opening iCloud, you will see that the address book icon is open.

Step 4: Close the address book under the iCloud project and pop up whether to delete the address book.

Step 5: Click "Delete from My IPHONE", then wait for deletion, and then open the address book to have a look.

Method 2: delete synchronously with iCloud.

First, open the setup options, select the email and contact columns, click New Account, and then select Exchange.

Second, fill in the configuration information casually, ignore the prompt that the system asks you that you can't connect to the server, and click Save directly; Press next.

Third, ignore the error message, save the configuration, and then start contact synchronization: click delete all contacts, and you're done.