Most fasting apps are just a countdown timer, but people running longer intermittent windows and multi-day extended fasts want to know what is actually happening in their body at each hour, and that physiology is opaque and scattered across blog posts. On top of that the timer itself has to be trustworthy: it needs to survive an app restart, keep running offline, and stay accurate across a fast that can last several days.
We built QoFast as a single cross-platform product shipping to both the App Store and Google Play, and modeled 13 metabolic milestones against elapsed fast time so the current phase is always visible rather than buried in an article. The timer is offline-first, surviving restarts and syncing to the cloud when a connection returns, and the live phase is pushed to native surfaces (Lock Screen, Dynamic Island, home-screen widget, Apple Health) so it stays glanceable without opening the app.
QoFast launched on iOS and Android as a free tracker with a Pro upgrade. The free tier covers intermittent protocols up to 24 hours, the 13 milestones with notifications, water, mood and weight logging, weekly stats, streaks and a 7-day history. Pro unlocks extended 3, 5 and 7-day fasts with guided prep and refeed phases, auto-cycling eating and fasting schedules, unlimited history, monthly analytics with zone-time distribution, and CSV export. Accounts support guest use or Apple, Google and email sign-in for cross-device cloud sync. The app is operated by Qorinx OU and is positioned as a wellness and tracking tool, not a medical device.
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