Challenge Achieved switches from boring "to-do list" concept to "challenge" concept. Motivate yourself, track your progress, share your challenges with friends, collect supporters and push your limits. Different kinds of challenges: One time challenge - Create a todo list, split tasks, track progress and reuse. Could be used for almost anything. Daily challenge - Set goals for practicing French language couple days a week or a daily run. Use it for daily motivation and recurring tasks. Number challenge - read 500 pages of a book, lose 5kg, save 1500$ for a new laptop. It's when you have numbers that you want to track.