Kanji Koohii - Remember the kanji; mnemonics, smart dictionary, flashcards, spaced repetition.
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.
Drops - Visual language learning.
WaniKani - Learn around 1,700 kanji and 5,000 vocabulary words in about a one to two years.
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 .
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.