Anki - Anki is a program which makes remembering things easy. Because it's a lot more efficient than traditional study methods, you can either greatly decrease your time spent studying, or greatly increase the amount you learn.
Memrise - Learn a new language with games, humorous chatbots and over 30,000 native speaker videos.
TOFU Learn - Learn vocabulary the easy way
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.
Discovery FlashCards - Discovery FlashCards is a unique free program that can help you study.
Flashcard Hero - Mac flashcard study app that saves you time memorizing information by keeping track of what you already know so you can focus on what you don't know.