What I might also like is multiple URL support.
If I want to use some videos in a presentation at University I first seek them all and copy them into the downloader.
After collecting all URLs I press downlaod and everything gets downloaded.
It saves lots of time and makes life easy.
The downloader I have oob my Widnows computer works that way.
Pretty nice.
If you want to improve music download here are some ideas:
1: [Optional] Add numbers in front of the file name
-> Helps for playlists without numbers in the name.
2: Combine it with easy tag
-> Before downloading the playlist you may edit the Album and Artist and such for every video
-> Use filename as tiitle
3: Support for different quality (up to 320 kbps)
Of course other updates are welcome as well

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