If you want to know how to turn off the screen without using the power button, then you should join the att customer service. The support team will let you know you need to open the app and click on the button tab. Also, you need to tick the power dialog. 1-855-436-9666 http://att.customer-servicephonenumber.com/
United States, Computer, To turn off the screen without using the power button join Att Customer Service 1-855-436-