Chronii: Time Tracking Made Simple
Published November 8, 2025
Chronii is a cross-platform time tracking app designed with privacy and ease of use at its core. Available for both desktop and web, it provides a streamlined way to track your time without the frustrations of cloud-based alternatives.
Features
Chronii focuses on the essentials of time tracking with thoughtful quality-of-life improvements:
- Privacy by design - your data stays on your device
- Smart timer suggestions based on your recent timers for faster workflow
- Time summaries by day, week, or custom selection for easy review
- Mark as logged to track which tasks have been logged or billed
- Automatic dark mode for comfortable use in any lighting
- Native feel interface optimized separately for desktop and web with a compact, efficient layout
Why I Built It
I built Chronii to solve the frustrations I had with Clockify for time tracking at work: cloud sync lag, inability to store sensitive task details, disruptions from updates and re-authentication, and no features for adding specific time segments or tracking billed time.
Technology
The app is built with a modern tech stack optimized for performance:
- SolidJS for a performant and lightweight frontend framework
- Electron to package as a cross-platform desktop app
- DaisyUI for a lightweight component library to accelerate design and styling
- SQLite for a portable local database, available in browser via sql.js
- Playwright and Vitest for comprehensive testing
Development Journey
From Prototype to Production
I initially built Chronii as a Flutter app with Firebase backend, todos, and notes; an experimental productivity suite that explored a broader feature set. While valuable as a learning platform, it suffered from performance issues and feature dilution that prevented it from effectively solving my core frustrations with Clockify. I rebuilt Chronii from scratch in Electron with SolidJS, focusing exclusively on time tracking to deliver a performant, native-feeling app optimized for privacy and simplicity. This focused approach yielded a much more performant and reliable, with faster development velocity.
Insights from Usage
As I used the app, I discovered areas of improvement I wouldn’t have found otherwise. For example, edge cases in state management that interrupted flow, refinements to how information is displayed to keep the interface compact and easy-to-use, and new relevant new features. I added task suggestions based upon the names of recent tasks to make it easier to jump back into ongoing projects, and added the “mark as logged” feature as I realised this would help me check off which tasks I had already billed. Off-the-shelf time tracking solutions always felt like an awkward fit, with many features I had no use for, but this product was now designed for someone doing exactly the kind of work I did, suited for routine use in my regular workday.
Web Deployment
However, I wanted something a little easier to share, and compatible with more devices such as phones. I developed tests to ensure integrity and integrated a web deployment target, using sql.js for in-browser database. This took some iteration to get working properly, but GPT-5.1-codex in Warp got things working in the end. I iterated on the UI using GLM 4.6 and Claude Sonnet 4.5 to improve the responsiveness of the design, as the compact edge-to-edge app layout needs a little adapting to work with larger desktop browser windows.
Try it out and experience time tracking that respects your privacy!