Insert from Drive in the Gmail Android app
It’s now easier for you to share files with friends and family—simply insert Google Drive files directly into your Gmail messages on your Android phone or tablet. If the file isn’t shared with the person you’re sending it to, you’ll get the option to change your sharing settings before you send it. And you’ll notice improved autocomplete suggestions for your contacts when composing messages—just start typing in the To, Cc or Bcc field to see better suggestions, faster.
These features will be rolling out over the next few days. If you aren’t already using the Gmail Android app, download the latest version from the Play store (https://goo.gl/3vcM7k