Instant Apps Enabled by Default
In 2016 Google debuted a feature called Android Instant Apps. Essentially allowing us to use an entire application without ever downloading it. Search for something like Wish or NYTimes, and you can find a cloud-based version of the app in Google Search or Chrome. Android Oreo instantly uses all aspects of the app without downloading it, and discards everything when you're done.
It's like a try before you buy type thing. Saving us time, space, and data by using apps on the fly. No longer install an entire app just to use it once. More information is available here.
This started rolling out in February of 2017 but is now fully working for everyone and enabled by default on Oreo. Technically, you can use it on Nougat following our instructions in the link above.