- Added an audible sound indication for every time the current problem changes to the next problem.

Release 2.0: - Sound effects updated to respond to the device volume settings. - Tap sound effect changed from a single sound for both correct and incorrect taps to be distinct sounds for each. - New sound effect added for time expired. - Speed setting moved from onscreen button to the Settings icon, but can be also displayed onscreen if selected in Settings. - New Help icon and corresponding Help screen.

Release 1.1 - Adds the ability to Stop. - Adds Setting to have static values for the 16 buttons for all 10 problems, rather than all button values changing for each problem. - Adds Setting to make a static button disabled if it is correctly used, thereby visually reducing the number of options with each correct answer.