Language Learning with Netflix - Use movies as study material for language learning

you-tldr - Get the tldr of any YouTube video in seconds

Duolingo - Duolingo is a free language learning app for iOS, Windows and Android devices. The app makes learning a new language fun by breaking learning into small lessons where you can earn points and move up through the levels. Read more about Duolingo.

tubecut. - The only YouTube downloader allows you to trim specific time

Caption - Open-source captioning tool to help find the right subtitles.

GIFit! - Quickly turn YouTube videos into GIFs (chrome extension)