Assuming you are utilizing the Yahoo Mail application for the iPhone or for Android, when you sign in you commonly stay signed in for all time except if you physically sign yourself out. The interaction to sign in is straightforward and is a similar whether you have an iOS or Android gadget.
Start the Yahoo Mail application. Assuming you're not yet endorsed into any mail accounts, you'll see the Sign In page. Tap Sign in with Yahoo.
2. Type your ATT Yahoo Mail username, email, or cell phone number related with the record and tap Next.
3. Enter your secret word and tap Next.
4. After a second, you'll be endorsed in and taken to the inbox.