Google's always experimenting with tiny improvements to its search experience with the hope of helping out users who feel like their wants and needs are stuck in the margins. Fortunately for them, after months of it hiding in the background, they can now finally access these experimental features through a new Labs section of the search app.
The first hint of Labs was picked up all the way back in February by 9to5Google with a few strings of code mentioning it in the beta of version 9.21 of Google. It was only in December that we were first tipped about the feature going public and right about now that people have really started to notice.
You should be able to see the new Labs item by tapping on the More tab in the Google app. From there, a list of features in testing should appear along with synopses on what they're intended to do. You can flip toggles for the features you want to try out.
Tapping on the Learn More buttons for each feature will bring up instructions on how to use them as well as certain caveats or extra steps you may need to take outside of the app. Currently, Google is workshopping pinch-to-zoom for text and image results and enhanced screenshot actions. And then, of course, there's the self-explanatory feedback button.
I bet we could fill a whole list of features we'd like to see on the app, but alas, we can only test what Google's actually working on. Ironically, after loads of updating on our end, this looks to be a server-side change, but you can check the Play Store for an update or download the latest from APK Mirror anyways.