Copoll - Language learning app

Copoll is built to prepare an environment for users to learn new languages. This is the first version of this App and users can learn German language so far, but it will cover English, French, Turkish, Farsi and etc in the near future. The users can learn these languages from English and Farsi so far and in future updates, users will be able to learn from more languages.
Users can learn vocabulary by observing pictures and listening to their pronunciations, which is one of the best methods to learn and memorize new words. There is also the grammar section which provides data for learners to learn how to use the learned words. Another section of the app is the exercise section which allows learners to practice what they have studied in the vocabulary and grammar section.
Users can go to next levels by passing the tests in the Test out section. There is also a review segment which provides an environment for users to review all the words that they studied.