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.
GoldenDict - The program has the following features: Use of WebKit for an accurate articles' representation, complete with all formatting, colors, images and links.
Fluently Beta - Write fluently in any language
Google Translate - Google's free service instantly translates words, phrases, and web pages between English and over 100 other languages.
Obstino - Obstino is your key to effectively learning, practicing, and retaining new words for a more robust vocabulary.
PONS - Germany’s most-trusted foreign-language dictionary. Includes language-learning materials, definitions, examples, pronunciation tips and a vocabulary trainer.