If you're not familiar with Gboard, it works like this. Download the extension from the App Store like you would any other app and Google will walk you through the installation process. Once it's the default option, Gboard will place a circular button at the top-left of the keyboard, allowing you to perform web searches without having to leave the app you're in. It'll also do the same for GIFs and let you type the name of your favourite emoji so you don't have to spend valuable time scrolling through trying to find it.
During its WWDC 2016 keynote, Apple announced a number of new features that cross over with Google's Gboard app, including an emojifier that can detect specific words and replace them with the relevant emoji. With web and GIF search, Google still maybe has an edge over its rival, but it's good to see both companies implementing more keyboard-centric features on iOS devices.