The Byki system takes an elementary, fundamental concept of learning a language — flash cards — and applies it to the strengths of computer desktop and iPhone interfaces. There are dozens of languages covered by Byki, with lists of cards provided by themselves and the ability for individual users to create their own. For each list of cards, there’s a 3-step process — look through the cards, see them in the foreign language and answer in English, see them in English and answer in the foreign language — then proceed to a multiple-choice quiz (foreign language questions with English answers). All throughout the words are read out in the foreign language and English, which helps the learning process. The free versions have a limited set of card lists; the paid versions have extensive lists. A strength is convenience: you can cover an exercise in a spare set of 15 minutes during a commute or waiting room. Good value app.