Maximize your Vocabulary and minimize your learning time. Vocab Tool will teach you words permanently through various customizable tasks, methods, and tempos using spaced repetition algorithms.
Spaced repetition is an evidence-based learning technique that is usually performed with flashcards. Newly introduced and more difficult flashcards are shown more frequently, while older and less difficult flashcards are shown less frequently in order to exploit the psychological spacing effect. The use of spaced repetition has been proven to increase the rate of learning.
Ideal for use in language courses, schools. Since you can use your own words in it, which you can even load from an XLS file.
It is completely free.