National flags of the world - Quiz 1.23

A game to learn the country flags of the world. For every flag, 4 possible answers.
Playable at different level : EASY, AVERAGE, HARD.

---- Regular Game ----
You can play with the flags of the 206 countries of the world to win the bronze (easy mode), the silver (average mode) and the gold (hard mode) medal.

---- Challenges ----
In addition to that mode, you can play 5 different challenges :
- EURO 2016 : countries participating the EURO 2016 competition (including the flags of England, Wales, Northern Ireland that aren't present in the standard game where only United Kingdom is represented)
- COPA AMERICA 2016 : countries participating the COPA AMERICA 2016 competition
- EUROPEAN UNION : countries from the European union (including United Kingdom, Brexit not being active yet !)
- UNION JACK : flags with the Union Jack
- FORMER FLAGS : former flags of current countries (e.g. Canada) or flags of former countries as the USSR or the spanish republic.