The full version was offered for free at one point. That’s how I got it. I’ve never been sure how safe it is from a privacy standpoint.

It does a lot, but can’t create uncompressed zip files. I discovered this recently when I was changing phones and wanted to grab a bunch of uncompressable stuff from my secure folder. Solid Explorer can but isn’t free.

I have Material Files installed (recently) but haven’t played with it yet.