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.
MDBG English to Chinese dictionary - English to Chinese dictionary with Mandarin pinyin - learn Chinese faster with MDBG!
LinguaLeo - The best online service for learning English.
Pleco - The #1 Chinese dictionary app for iOS and Android
Rosetta Stone - Rosetta Stone is the world's most popular software for learning languages. It is offered at a cost of just $169 when purchased outright, but it is also possible to purchase language programs in a subscription format that offers ongoing support.
wenlin - Wenlin Software for Learning Chinese