Lunar Fasting vs JustFast
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
Lunar Fasting
Read full descriptionHide full description
Fasting, water, weight and calories — tracked against the real lunar calendar. Snap a photo of your meal and get a calorie estimate, with Apple Intelligence keeping the photo on your iPhone. INTERMITTENT FASTING Log your meals and the app works out your fasting windows automatically — no timer to start or stop. Choose a protocol from 12:12 to OMAD; past days are always judged by the protocol that was active at the time, so changing your goal never rewrites your history. CALORIES FROM A PHOTO (Pro) Take a photo of your meal and the app breaks it into dishes and estimates calories for each portion. You choose who does the counting: • Local — Apple Intelligence on your device (iPhone 15 Pro or later, iOS 27): the photo never leaves your phone, no key or internet needed. • Cloud — OpenAI, Qwen, Gemini or DeepSeek using your own API key. In Auto mode the app tries Apple Intelligence first and falls back to your key. You can also type calories in by hand — that's free. MY FOODS Every food you log is saved to your library: favorites, recent items, servings (×2, ×3) and one-tap repeat of a previous meal. WATER Log water in one tap — it goes straight to Apple Health. Your daily goal is calculated from your weight (33 ml/kg) or set manually. WEIGHT Weight history with a chart and a reminder to weigh in regularly. WIDGETS Small, medium and large widgets: today's lunar day, fasting timer, water, calories eaten and burned, plus quick buttons to add water, log a meal, add a saved food or snap a photo. GOOGLE HEALTH → APPLE HEALTH Wear a Google-connected band? Sign in with Google and the app copies workouts, heart rate, steps, energy, distance and sleep into Apple Health, without duplicates. Optional, off by default. REAL LUNAR DAYS Not the generic calendar month: actual lunar days from moonrise to moonrise at your location, with moon phases. ACTIVITY INDEX AND FORECAST (Pro) Each day gets one activity score (0-100) from your steps, active energy, workouts and stand hours. See trends by lunar day and moon phase, and a forecast for the whole lunar month ahead. DAY RATINGS AND STATISTICS Rate each day on your own criteria — mood, energy, sleep, productivity — and see charts for activity, steps, water, weight, calories and ratings over a cycle, 3/6/12 months or your full history. SMART SCHEDULE Optional reminders for water and your eating window, built from your wake/sleep time and fasting protocol, with quick-log buttons right in the notification. PRO (SUBSCRIPTION) Photo calories, the full lunar-month forecast and the activity index are part of Pro, which includes a 3-day free trial. The subscription renews automatically unless cancelled at least 24 hours before the end of the current period; manage or cancel it anytime in your Apple ID settings. PRIVATE BY DESIGN No account and no server of ours. Your data lives on your device and in your Apple Health. We collect only anonymous usage statistics (which features are used) — never your meals, weight, photos or health data. If you add your own OpenAI, Qwen, Gemini or DeepSeek key, a photo goes straight to that provider; the developer never receives or stores it. Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ Privacy Policy: https://klukyanov.ru/moonactivitytracker/privacy/
JustFast
This app offers a straightforward intermittent fasting timer. It focuses on tracking your fast with a clear, calm interface, providing insights into metabolic stages without gamification or pressure. It prioritizes privacy with on-device data storage and no accounts.
- One-tap start and stop
- Live timer with accurate timekeeping
- Metabolic milestone tracking
- Plain-language explanations of milestones
- Adjustable start/stop times
- Ongoing notification for duration
- Simple history of past fasts
- 18 languages and dark design
Read full descriptionHide full description
Fasting is a beautifully simple intermittent-fasting timer that does one thing well: it tracks your fast. No goals to hit. No streaks to protect. No accounts, no ads, no clutter. Just tap once to begin, and a calm live timer counts your fast while a glowing ring fills toward the next stage your body moves through. WHY IT'S DIFFERENT Most fasting apps pile on dashboards, reminders, and pressure. This one strips fasting back to its essence — a clear timer you can glance at and put away. It's designed to feel quiet and focused, not gamified. WHAT YOU GET • One-tap start and stop, with a big, satisfying button • A live timer that keeps perfect time across restarts, time-zone changes, and daylight saving • Metabolic milestones — the ring fills toward the next stage (blood sugar settling, glycogen burning, fat burning, ketosis, autophagy, and more) • Tap any milestone for an honest, plain-language explanation of what's happening in your body • Forgot to start the timer? Just tap the ring to fix your start time. Forgot to stop? End your fast at the right time after the fact. • An ongoing notification shows your current duration at a glance • A simple history of past fasts — swipe to delete • 18 languages and a clean dark design HONEST BY DESIGN The milestone descriptions are written plainly and honestly. Where the science is still early or based mostly on animal research, we say so. This app is a timer and an educational companion — not medical advice. PRIVATE BY DEFAULT Your data stays on your device. There are no accounts, no sign-ups, no tracking, and nothing is uploaded. Fasting works for 16:8, OMAD, alternate-day, extended fasts, or any schedule you like — because it never forces a schedule on you. Note: Fasting is not a medical device and does not provide medical advice. Talk to a healthcare professional before starting any fasting regimen, especially if you are pregnant, nursing, taking medication, or have a medical condition.
Screenshots
Verdict
The clearest difference is in-app purchases: JustFast at none against Lunar Fasting's 2. On price, update cadence, ads and device support there is nothing between them.
Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS
Both are free to download. Lunar Fasting sells 2 in-app purchases, starting at $0.99 per 7 days. JustFast asks for nothing beyond the download.
Both ship on a similar rhythm, roughly fortnightly. Both last shipped on October 31, 2026.
| Parameter | Lunar Fasting | JustFast |
|---|---|---|
| Price | Free | Free |
| Rating | — | 4.5 (2 ratings) — better |
| Number of ratings | — | 2 — better |
| Update frequency | Fortnightly | Fortnightly |
| Ads | No | No |
| In-app purchases | Yes | No — better |
| Monetization | — | Free |
| Devices | iPhone, iPad | iPhone, iPad |
| Requires iOS | 17.0 — better | 18.0 |
| Further details — not scored | ||
| Size | 9 MB | 20 MB |
| Age rating | 4+ | 4+ |
| Developer | Kirill Lukyanov | Vitalii Vyrodov |
In-app purchases
Lunar Fasting
- Pro — Week3 Days trial$0.997 Days
- Pro — Year3 Days trial$24.991 Year
JustFast
No in-app purchases









