Fastiya is now on the App Store — download free 🔥
Download on theApp Store
Now available on the App Store

Fast Smarter. Live Longer.

Track every hour your body transforms. A premium intermittent-fasting app with AI coaching, live metabolic states, and Live Activities.

Download Fastiya onApp Store See how it works

No account required. No paywall on day one. Just you, a timer, and every hour your body transforms.

0Metabolic states
0Fasting protocols
0Accounts needed
🔥 0

Good morning

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WED17
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Live body state 🔥 Fat burn starting Now it's working. Sipping water can ease hunger cues.
08:02:55 Elapsed · 44%
StartedTue, 1:41 AM
18h goalTue, 7:41 PM
0–2h
Hour 0
Live metabolic states
PHASE 01

Digesting

Blood sugar stabilises as your last meal is processed.

Food is being broken down

Scroll to watch your body transform
See what's happening inside

Six phases. Every one of them tracked.

Set your protocol, start your fast, and watch your metabolic state evolve in real time — hour by hour.

01 0–2h

Digesting

Blood sugar stabilises as your last meal is processed.

02 2–4h

Absorbing

Insulin drops. Your body starts burning stored fat.

03 4–8h

Fat Burning

Glycogen depleted. Ketones rise as primary fuel.

04 8–16h

Ketosis

Full ketosis. Mental clarity and sustained energy.

05 16–24h

Deep Ketosis

Growth hormone surges. Deep metabolic regeneration.

06 24h+

Deep Repair

Cellular cleanup begins — damaged cells recycled.

Live Activity

Your fast, live on your lock screen

Set your protocol, start your fast, and watch your metabolic state evolve in real time. Your lock screen and Dynamic Island update live so you never lose track.

  • Live Activity on lock screen & Dynamic Island
  • 6 metabolic phases with live body-state descriptions
  • Know exactly when you hit ketosis & autophagy
Wed, Jun 24
10:28
OROFAST FASTING
17:59:43
18:6FAST
Digesting Insulin elevated
Meet Oro · Powered by AI

An AI coach that actually knows your data

Ask Oro anything — how your week went, what to eat to break your fast, why you feel tired at hour 14. Oro knows your data and gives you real answers, not generic tips.

  • Context-aware: knows your metabolic state, streak & patterns
  • Answers based on your personal fasting history
  • Powered by AI via a secure server-side proxy
OOroonline
Why do I feel tired at hour 14?
You're entering deep fat-burning — glycogen is low and ketones are still ramping up. A slow breath or short walk can help ride out the hunger wave. 💪
How is my week going?
Health Insights

Every metric that matters, in one place

Bio-age, fat burned, sleep quality, activity zones — all in one place. See exactly how consistent fasting is moving the needle on your long-term health.

  • Bio-age score updated with each fast
  • Steps, floors, and cardio trend tracking
  • Streak tracking and milestone badges

Insights

Suggestion Body energy improved from 45% to 67% vs last week.
Body Energy ›
67%Good
Stress ›
33%Low
Recovery ›
59%Building
Exertion ›
64%Moderate
Your fast, your way

Pick the protocol that fits your life

12:12 16:8 18:6 20:4 OMAD
Fastiya Journal

The science, in plain English

Research-backed reads on fasting, metabolism, and how your body changes hour by hour.

Frequently asked questions

Everything you need to know

Open Fastiya, select your fasting protocol (e.g. 16:8 or 18:6), and tap "Start Fast". Your timer and metabolic tracking begin immediately.

Tap the active timer on the home screen and press "End Fast". Your progress is saved to your streak and history.

Fastiya tracks six metabolic phases as your fast progresses: Digesting (0–2h), Absorbing (2–4h), Fat Burning (4–8h), Ketosis (8–16h), Deep Ketosis (16–24h), and Deep Repair (24h+).

No. Your fasting data stays on your device and is never sold or shared with third parties. AI coaching requests are transmitted over TLS-encrypted connections. See our Privacy Policy for full details.

Go to iOS Settings > Your Name > Subscriptions, find Fastiya, and tap Cancel Subscription.

On any paywall screen, tap "Restore Purchases" and sign in with the same Apple ID you used originally.

Begin your journey today

Ready to start tracking your metabolic transformations? Download Fastiya and watch every hour your body changes.

Download Fastiya onApp Store

Fastiya is a wellness tool, not a medical service. Always consult a qualified healthcare professional before beginning any fasting programme.