Boost is a countdown timer and stopwatch for Android, built solo with Flutter and Dart. It runs entirely on the device, with no account and no network, and it anchors every session to the system clock so the time left is still correct after you switch apps or the process is closed.
Boost has no menus, tabs, or settings pages. The whole app is one screen that changes with what you are doing. Every image below is a capture of the running application.
A timer is a deceptively simple thing to ship. The work is in everything that happens once the screen turns off.
Rather than decrementing a counter every second, Boost stores the start and target timestamps and derives the remaining time from the system clock. A foreground ticker only drives the display. Android is free to suspend the process, and when the app comes back the numbers are still right.
Timer mode, running and paused flags, the start and target epochs, and accumulated
pause time are written to local storage through shared_preferences. The app
observes the Android lifecycle and rebuilds its state on launch, so a session continues
across an app switch or a restart.
Choosing a duration uses a looping ListWheelScrollView rotated to run along
the bottom edge of the screen, with fixed-extent snapping. It reads as part of the
display rather than a form control, which keeps the app to a single screen.
There is no account, no backend, no analytics, and no third-party SDKs. Everything is stored locally, which is why the app works with no connection and why its privacy policy has nothing to disclose.
Also in the build
Boost is a small app, shipped solo from first commit to the Play Store listing. The same approach applies to the web, backend, and mobile work I take on under contract.