Google is testing a new sign-in page for Gmail and other Google services that will allows users to login to multiple Gmail accounts from an easier to user screen. Users are already allowed to login to multiple Gmail accounts while logged in to one Gmail, but this new feature makes it easy to do that.
The new feature called “Account Chooser” will display multiple accounts on the screen, of course you have to add all the accounts you want to sign-in to. Once added it will display name, email address and profile pic if already added one, users can click on the account they want to login.
The account chooser feature is not released publicly and we are not sure when it will be launched for everyone. But if you would like to use this feature you can opt-in to use this feature from this link. You can add other accounts here, if you don’t see all your accounts here.