Once you receive the drawing from the other user, you will have to guess what they drew. When guessing, the strokes of the drawing will appear in the same order as the user drew them. You can jump to the finished drawing by pressing the button on the upper right part of the canvas.
The number of letters the word has can be found under the canvas, while the category it belongs to will be found at the top of the screen.
If you guess the word, you may be rewarded with coins, a chest with different prizes, or both. You will get coins for the first 20 guesses of the day and you will receive chests provided that you have room in the chest bar.