But xmanager is not providing the apk, so the project doesn’t do anything illegal.
Also if you root your phone (not illegal for some devices) you can install any app from the store and the apk is just there… on your device, which you can then patch.
This is how I do it. I have all my media on a raid 5 tho. Broken hdds are unavoidable in the long run, so I want protection for that. If something goes sideways at rebuilding, so be it. Most of the movies and shows I’m wondering what I save them for anyways. My music collection is worth more to me and backed up properly. Same goes for my personal stuff.