Tiny Calendar Check

Tiny Calendar Check is a very simple, very small calendar checker app — a native Chrome extension that lets you create multiple calendars (for example, Workout) and mark each day as completed. Tap a day to check it off; it's fast, lightweight (under 1 MB), and intentionally minimal—no permissions, no data collection, and no ads.

The app also features a Reports section with basic statistics to review your progress. It’s completely free, with optional donations to support development.