Earlier this year, Google added quick action buttons in Gmail. They appear on messages in the inbox, and allow users to take action on them without even having to open them.
Initial examples included things like checking in for flights, responding to event invites, reviews, confirming registrations, etc.
Today, Google announced that it has added more types of quick actions.
"For example, you can rate and review restaurants you ordered from on Seamless and even modify OpenTable reservations—all without opening an email," writes Google's Claudio Cherubino in a blog post. "And for the deal lovers out there, you can conveniently save a promotion from Google Offers with one click, making it easy to find and buy it when you’re ready."
"If you’re an avid uploader of YouTube and Vimeo videos, you can view finished uploads with a single click with the new 'View video' button," Cherubino adds. "Similarly, you can also speedily open a Dropbox folder or Google Docs, Sheets, and Slides that have been shared with you."
For documentation on how to add this stuff to your own emails, go here. Google says it will be adding more types of actions.