A mainspring is the spiral torsion spring that provides power for mechanical watches and clocks. Mainspring (the app) should provide all the power you need as a mobile phone stopwatch.
- No banner ads - just donate from the Preferences page if you like the app.
- Lap time records with minimum, maximum, and average lap times.
- Press and hold the start/stop/lap buttons to enlarge them.
- Use the "unlap" and "unstop" menu items to undo accidental touches of the Lap or Stop buttons.
- Portrait and landscape layouts.
- Haptic feedback option when pressing start, stop, or lap buttons.
- "Talking stopwatch" will recite lap time and stop time so you can stay focused on what you're timing.
- Optionally prevent the phone from sleeping so you don't miss any button presses.
- Use the volume buttons for start/stop or start/lap/stop actions.
- Notification icon provides quick access back to the stopwatch from within other apps.
- Lock-in a preferred screen orientation.