Google+ has a feature where you can insert Auto Backup photos from your smartphone and tablet, now this feature has arrived on Gmail as well. This means that you will be able to insert your Auto Backup photos from your phone into Gmail messages on the web using the new “Insert Photo” button. This button is located on the bottom toolbar of new Gmail messages and lets you include photos that have been backed up from mobile devices. On clicking the button, you will get a grid interface with tabs for recent photos and all of your curated photo albums.
The new feature will allow you to share entire album in an email message. You can also resize photos by dragging in from the corners. Google says that this new feature will be rolling out today in Gmail on the web.
SOURCE: Official Gmail Blog