A simple number line game to improve your abilities when adding or subtracting positive and negative numbers. Simply tap on the number line to select the answer to the displayed equation! The displayed number line helps you visualize the solution! Tap directly on the answer or start at the first number and drag the selector the correct direction and distance to the answer! Your iPhone can even vibrate as you slide along the line! Tracks of number of equations solved by type (addition of a positive number, addition of a negative number, subtraction of a positive number, and subtraction of a negative number) and the number solved correctly on the first attempt! How does your score compare to your friends or classmates!? Having trouble with subtraction of negative numbers? Preferences allows you to show negative number in parentheses to make the equation more clear! Allows you to control which type of equation you get... or let the app select either addition or subtraction of a negative or positive number!