Adding numbers without using your fingers is a great skill to practice. With this app you can practice this skill of adding numbers in your mind and use different techniques to do this faster. This is a fun game that can be played by people of all Age. Just add the numbers being flashed in front of you mentally and then answer the sum of the numbers flashed. You can vary your speed and the number of digits as per your comfort levels. Don't forget to enjoy while you play and get faster. All the best.