For hosting common files it's ok. Also it is on Android too do, great to transfer files between your Windows and your phone. But if you want better security you have to subscribe a monthly offer.
Dropbox - Online Sync and File Sharing
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.
Google Drive - Access and sync your files anywhere
Memrise - Learn a new language with games, humorous chatbots and over 30,000 native speaker videos.
Mega - Secure File Storage and collaboration
Busuu - Join the global language learning community, take language courses to practice reading, writing, listening and speaking and learn a new language. Learn English with busuu's .