Ignore those who are saying that this game is waste, because games are being played for entertainment in your free time.
Clash royale’s concept - you are the king and have an army which contains amazing cards with different powers and you have to fight with opponent choosen by the game from around the world.
Layout and design-Graphics of this game are amazing , one can easily understand its format because it have clear cut theme of repersentation.for example-
Features and functions- I already told about it in pics.
Usefullness-Directly there is no use of this but those who like games too much can play this for all 24 hours of a day.