LearnObit - A tool for your learning, like Anki & Workflowy in one

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.

Simply Learn Languages - A phrasebook of 50+ languages for traveling (with audio)

TOFU Learn - Learn vocabulary the easy way

Quizlet - Quizlet allows you to review and create flashcards for a variety of subjects, such as math and reading.

Kommit - Flashcards / Spaced Repetition System with text-to-speech