Words With Friends achievement levels are an indication to show your progress in the game. You can level up by completing achievements to earn points or, as Words With Friends calls it, pages. The pages then go towards unlocking a book which counts as going up a level in the game. At the top of the Games screen, you can view your current level and progress in reaching the next level. All of your completed and available achievements can be found in your profile. There are four different categories of achievements being Words, Games, Trials, and Friends. Some achievements called, Lifetime Achievements, keep track of your progress since you first joined Words With Friends. Each book progressively takes more pages to unlock making it more difficult to level up each time. You can view the books on the progress map next to the achievements tab. Tapping on an unlocked book will display the title of the book and a quote from the book. Tapping on a locked book will display how many pages it takes to unlock it.