Fast 2 Fit
Your Personal Fasting Guide
$1.99 · Designed for iPad. Not verified for macOS.
Track intermittent fasting with personalized phase timing, real-time biological state visualization, Apple Health integration, and smart notifications keep you motivated.
Transform your fasting journey with personalized guidance tailored to YOU.
Fast 2 Fit is the intelligent intermittent fasting companion that adapts to your unique biology. Unlike generic fasting timers, Fast 2 Fit estimates personalized phase transitions based on your age, gender, activity level, and last meal type — so you get a timeline built around you, not a generic countdown.
PERSONALIZED FASTING PHASES
Your body is unique. Fast 2 Fit uses a personalized moderator system to estimate when you'll reach each biological phase:
Absorption → Post-absorption → Ketosis → Autophagy → Deep Autophagy → Peak Autophagy
A young, active person on a low-carb diet may reach estimated ketosis in as little as 5 hours, while others may take 22+ hours. Fast 2 Fit estimates YOUR timeline.
EXERCISE INTEGRATION
Log a workout during your fast? Fast 2 Fit reads your Apple Health workout data — no manual entry needed — and adjusts your phase timing, since exercise depletes glycogen faster and can speed up the shift into fat-burning mode.
FASTING PROGRAMS FOR EVERYONE
Choose from popular protocols:
• 16:8, 18:6, OMAD (One Meal A Day)
• Extended fasts: 24h, 36h, 48h, 72h
• Weekly Plans — pre-designed 7-day sequences to automate your habits and keep you on track
• Demo mode for testing
ON YOUR WRIST TOO
Fast 2 Fit includes a full Apple Watch app, so you can start, track, and check your fasting phase right from your wrist — synced automatically with your iPhone.
LIVE ACTIVITY & WIDGETS
Keep your fast visible without opening the app: add a Home Screen widget, or track your countdown on the Lock Screen and Dynamic Island with Live Activity.
STAY MOTIVATED
• Streak tracking — build consistency with consecutive day tracking
• Streak Preservation — "get back on the horse" logic that recognizes your progress even if you need to scale back a difficult fast, so you don't lose your momentum
• Trophies & achievements — earn rewards for milestones
• Confetti celebrations — celebrate completed fasts
• Smart notifications — get notified when you enter new phases
WEIGHT TRACKING
Seamlessly syncs with Apple Health to track your weight progress. See your 6-month trend with beautiful charts.
INTELLIGENT NOTIFICATIONS
• Phase change alerts ("You've entered ketosis!")
• One-hour countdown reminders
• Eating window reminders to maintain streaks
POLISHED DESIGN
• High-performance design with smooth animations
• Native support for Light and Dark modes
• Clean, distraction-free interface optimized for focus
PRIVACY FIRST
All data stays on your device and in your personal iCloud. No accounts, no servers, no tracking.
Fast 2 Fit's phase timelines are personalized estimates based on established fasting research, not a medical measurement — always listen to your body, especially during extended fasts.
Ratings & Reviews
- This app hasn’t received enough ratings or reviews to display an overview.
The developer, Bjoern Ruthberg, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Collected
The developer does not collect any data from this app.
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- Bjoern Ruthberg
- Size
- 18.2 MB
- Category
- Health & Fitness
- Compatibility
Requires iOS 26.2 or later.
- iPhone
Requires iOS 26.2 or later. - iPad
Requires iPadOS 26.2 or later. - Mac
Requires macOS 26.2 or later and a Mac with Apple M1 chip or later. - Apple Vision
Requires visionOS 26.2 or later. - Apple Watch
Requires watchOS 26.2 or later.
- iPhone
- Languages
- English and Norwegian Bokmål
- Age Rating
13+
- 13+
- Infrequent
Medical Treatment information
Contains
Health or Wellness Topics
- Copyright
- © 2025 Bjørn Ruthberg
