Gmail has been known for its organization, spam protection and more, and now it is beginning to offer those features to users without a Gmail account with Gmailify. The new feature, Gmailify, lets you sign into the Gmail app using your Yahoo, Hotmail or Outlook account and use it as if it were a Gmail account — including account management, folders, spam protection and all of the other great Gmail features. In addition, you'll now have Google Now capabilities with the other accounts, meaning flight information, purchases and more will create Google Now cards just the same way a Gmail account does.
Gmailify links your existing account to Gmail so that you get all the bells and whistles—spam protection, inbox organization and even Google Now cards based on your mail—without having to leave your current address behind.
To get started, all you need to do is open the Gmail app, sign into your other accounts and then enable Gmailify. If for some reason you don't want to keep your accounts linked, you can always unlink them at any time. To start, it will only work with Yahoo, Hotmail and Outlook.com accounts, but Google plans to add additional email providers in the future.
Source: Gmail Blog