How to challenge your friends:
Step 1: Solve 10 (or 5, or 20) puzzles and get the link to the Challenge
Step 2: Share the challenge link with your friend
Step 3: After your friend finishes the puzzles, there will be a link to the scores
Let's PLAY!
4 Numbers! or Follow @4nums_game to get 4 Numbers puzzle of the day, everyday.