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.
Subtitles Downloader by Checksub - Sometimes you may want to export or edit the subtitling of Youtube videos that you have uploaded or that you're fans of.
Drops - Visual language learning.
YouTube Transcripts - Turbocharged SEO with cheap, fast & accurate transcripts
Clozemaster - Learn a language through mass exposure to useful vocabulary in context.
Universal Word - Translate YouTube subtitles into multiple languages