It's a timer app with no sound & only vibration.
All features are completely free to use.

- Unlimited preset timers
- Timer can be specified up to the number of seconds
- Set labels and colors for timers
- Notification with strong vibration while the app is running
- Vibrate notification up to 60 times even in the background
- Icon badge display while timer is running
- dark mode

URL scheme:
vibrationtimer://