No opponent needed

Practise against the computer

A contest needs an opponent, and one is not always in the room. The app ships a computer player at three speeds, so a student can rehearse under real time pressure on any ordinary evening.

No opponent needed

Choose your opponent

Every opponent plays the same ten questions — five single-digit numbers each, adding and subtracting, no complements required. What changes is how fast the numbers flash and how good the opponent is.

How a match works

How a match works

  1. Watch the numbers
    Each question flashes one number at a time and then clears. Nothing stays on screen, so the running total is held in your head — the same way it works in a real contest.
  2. Tap in your answer
    When the last number has gone, type the total and lock it in before the timer runs out. You are told straight away whether it was right, and what the answer was if it was not.
  3. Beat it to the finish
    The computer is answering the same question at the same moment, and it does miss some. Whoever has more right at the end of the ten wins — so it is worth answering even when you are not certain.
Rather play a person?

Rather play a person?

The live duel puts you against a friend on another device, on the same questions at the same moment. One of you starts it and shares a link.

Duel a friend