See What Is Taking Up Space On Your Device With Grid Size File Manager
"The visual representation is clean and easy on the eyes, but items with smaller file sizes are too small to have labels. Unlike similar desktop software I've used before, though, that's quickly remedied with a simple pinch to zoom."
If you are a visual person, preferring to see boxes rather than numbers when determining what is taking up space on your device, here's an app for you. Not only can you see what is taking up space, but you can use this as a file manager as well.
There is an ad-supported free version, with the ad-free version costing $0.99 and it should work on any device. Let us know in the forum if you try it.