The worst is when an android app is clearly an iOS port. E.g Patreon app saves all files under a generic name rather than the one you get when saving the same file from a browser, because I guess on iOS it just goes into your camera reel without a filename anyway. Or how Bluesky app just straight up says "saved to your camera reel" and puts it in your DCIM folder, with no option to specify a different location.