SOL — Fasting Timer & Tracker

SOL (솔) is Korean for pine tree. Like the pine that endures through every season, SOL stands with you through every fast.

WHAT MAKES SOL DIFFERENT

Most fasting apps just show a timer. SOL shows you what is happening inside your body as the hours pass, with the research behind it.

As you fast, SOL guides you through eight phases:
Fed State, Insulin Dropping, Fat Burning, Ketosis, Autophagy, Deep Autophagy, Growth Hormone Surge and Immune Reset.

FEATURES

• A calm timer with a progress ring and phase markers
• Your fast on the lock screen and in the Dynamic Island
• All 8 phases explained, with links to the published studies
• A goal dial from 12 to 72 hours, or an open fast with no limit
• Started earlier? Set the time you last ate, and correct it later
• Switch the timer between time elapsed and time to go
• A daily reminder to start your fast
• Your Journey: stats, streaks, a 7 day view and your history
• Edit, add or delete past fasts
• Guidance on breaking your fast gently
• Home screen widget
• "Start my fast" with Siri
• Share your results with a beautiful card
• Light and dark mode with handcrafted watercolor textures

FASTING TOGETHER

If you like, join the live count of people fasting right now. It is optional, anonymous and off until you turn it on.

YOUR DATA

No account, no ads, no tracking. Your fasting data stays on your device unless you choose to join the community count or turn on iCloud backup.

DESIGNED WITH INTENTION

SOL is inspired by the simplicity of nature. No clutter and no paywall. Just you, your fast, and a clearer picture of what your body is doing. SOL is free. If you enjoy it, you can leave a tip.

ABOUT THE SCIENCE

Phase information is based on peer-reviewed research, with direct links to the sources. Some findings come from animal studies, and every body responds differently. SOL offers general wellness information and is not medical advice. Please talk to a doctor before fasting, especially for longer fasts.

Begin your fast. Know your body. Grow like the pine.