What are some alternatives?
When comparing aDownloader and 4k Video Downloader, you can also consider the following products
qBittorrent - Lightweight and open source torrent client that runs on all major platforms.
youtube-dl - A small command-line program to download videos from https://alternativeto.
µTorrent - Looking for a torrent site to download movies, music and more? Choose from top torrent sites like The Pirate Bay, RARBG, 1337X, and dozens more. (October 2019)
Youtube-DLG - A cross platform front-end GUI of the popular youtube-dl written in wxPython.
Deluge - Deluge is a full-featured BitTorrent client for Linux, Unix and Windows.
Video DownloadHelper - DownloadHelper is a tool for web content extraction.