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.
Lion (LEO dictionary) - Translate words on your screen with a single mouse click!
Fluently Beta - Write fluently in any language
PONS - Germany’s most-trusted foreign-language dictionary. Includes language-learning materials, definitions, examples, pronunciation tips and a vocabulary trainer.
Obstino - Obstino is your key to effectively learning, practicing, and retaining new words for a more robust vocabulary.
Google Translate - Google's free service instantly translates words, phrases, and web pages between English and over 100 other languages.