The Esperanto language was invented by L.L. Zamenhof in the late 19th century, with the hope that it would foster communication an international understanding by becoming a universal second language. Though this dream went unrealised, Esperanto remains the world's most enduring artificial language.
Liberation Philology Esperanto helps you build your Esperanto vocabulary in a convenient format available wherever you take your phone. It presents 1157 levels of vocabulary, each of which tests your ability to match a group of ten Esperanto words with their English equivalents. Your answers are immediately confirmed or corrected, and whenever you feel you've mastered a level, you can move on to the next. Periodic cumulative levels are interspersed among these to reinforce your knowledge (giving a total of 1300 levels) and you can also review the word list at any point.