A big part of Android Go is a focus on slimmer, less data-hungry apps that'll work on a wider variety of hardware, including the less expensive and less advanced devices that are popular in countries around the world. As such, Files Go helps users get the most out of their phone's storage. It recommends apps that aren't used often for removal, helps get rid of "spam and duplicate images" and helps users find everything on their phones by file type. The app also lets users files between phones without an internet connection, although it's still not totally clear how that works just yet (one screenshot indicates Bluetooth is involved).
The app is available now for anyone who wants to give it a shot. Sengupta tweeted that the company was looking for feedback, and it doesn't look like there are any restrictions on who can install it. But given how briefly it was live before, it's entirely possible that Files Go will only be live for a limited time -- at least, until it's out of beta.