I wanted a simple app for downloading youtube playlists but I couldn't find one so I made one. There is still lots I want to do with it but for now it does everything I need.
I was going to suggest yt-dlp, but this seems to be for android... right? In that case, I don't know if yt-dlp works there.
Anyway, for those on PCs, you can use yt-dlp "PLAYLIST_URL".
Some useful options:
--download-archive videos.txt: this will keep track of downloaded files in case you want to interrupt an continue later. You can change the filename videos.txt to whatever you want.
-R infinite --file-access-retries infinite --fragment-retries infinite --retry-sleep http:exp=1:20 --retry-sleep fragment:exp=1:20 --retry-sleep file_access:exp=1:20 --retry-sleep extractor:exp=1:20: infinite retries for different error types, for those with unreliable connections.
-o "%%(playlist_index)s - %%(title)s.%%(id)s.%%(ext)s": output file format
--cookies cookies.txt: if it's a private list, you will need to provide your (yt-logged-in-)browser cookies. See cookies.txt add-on.