I used to run Nextcloud locally, and could open it up on phones, tablets, etc. But I recently stopped using it, since it's no different than SFTP (Nextcloud just has a web UI to manage / view files and looks nice is all).

I got a NAS device hacked once, and watched people try to copy my stupid .MP4s/.MKVs off it, which is strange since all that's readily available on the web anyway. They were probably looking for sensitive info, but there wasn't any lol.