We’re talking about the possibility to load a picture and look up related images online. It’s kind of like a visual equivalent of Shazam in some ways.
For some reason, Google has decided not to make it an available feature on mobile devices, which means you can’t use a picture as your search query on Google from your phone (which is a bummer if you’re a foreigner and don’t know the name of something).
So here’s a quick fix for that.
Go on https://reverse.photos/ and click “Select Image” to load a picture from your gallery. Then click “Reverse Search” and you’ll get results that are similar to the picture you’ve uploaded.