Specifically, Google has just released a Files update for users, adding support for external storage via USB On-the-Go
In addition to USB drive support, the new app update also allows users to view the entire directory structure for external and on-device storage. This means users no longer have difficulties tracking files or moving them to specific folders without resorting to traditional Android file search methods.
Essentially, Files is now the most feasible solution for file management on Android devices and is a handy method for those who frequently transfer data back and forth.
Download Files and install it here: Files for Android
Explore more Android file management options beyond Google's Files, such as Root Explorer and ES File Explorer. To understand the strengths of each app, check out the article comparing Root Explorer and ES File Explorer here.