Experience Points (XP) are used to level up and earn rewards in the game. Your Experience Points tier can be found in the purple icon at the top of the screen under your avatar image. You earn Experience Points each time you complete a matching level in the game.
Levels refer to the matching levels in the game that you have last completed or are currently on. Your current Level can be found in the green box at the bottom of your screen. Each time you win a level you will learn Experience Points.