This move now allows Google to position Gmail as the all-in-one solution for your email needs. Most recently Google said you could ”Gmailify” your Outlook.com/Hotmail or Yahoo address, which meant advanced features like spam blocking and Google Now would talk to your non-Google email.
The version 6.4 update is rolling out in the Play Store, or you can get it now from APK Mirror.
The impact on you: If you’re a fan of Gmail but had to turn to another email app for your company mail, this gives you the ability to keep everything inside of one application. However, Gmail doesn’t connect as deeply to Office 365, so if you rely on Microsoft’s cloud for sharing documents, opening attachments, or integrating with other Microsoft services you may still wish to use the official Outlook app.