Know exactly what to lift today.
Fit4i builds your gym program, fills in the working weights and runs your progression — sets, reps and loads planned for every session.
Program · Working weights · Progression · Deloads
Fit4i is a gym workout tracker for iPhone that adapts to your recovery.
See your personalized plan before creating an account.
7 days of Pro · No card required · Works without a wearable
- Automatic progression
- Working weights filled in
- Recovery-aware adjustments
- Nutrition tracking
Built for Apple Health
Reads sleep, HRV, resting heart rate and blood oxygen — with your permission, read-only.
Designed for iPhone
A native iOS app. Works with Apple Watch data via Apple Health, and with Polar devices.
Privacy-conscious
No ads, no data selling, no tracking across apps. Food photos are analysed and discarded, never stored.
Training and nutrition in one app
Workouts, recovery, calories, protein, fiber, water and body weight — one place, one plan.
How Fit4i works
Four steps from your setup to a program that runs itself.
Set up once
Pick your goal, experience, equipment and schedule. Fit4i builds your program — days, exercises, sets, reps and starting weights included.
Muscle gain3 days a weekBarbell + dumbbellsHome or gym45-min sessionsInjury-awareTrain with clear targets
Every set shows what to lift: the weight and rep range are pre-filled from your plan, with a rest timer in between. Logging is two taps.
Set 1 of 560 kg× 6–12 repsProgress automatically
Reach the top of the rep range and the weight moves up next session. Volume waves and deloads are scheduled for you — no spreadsheet required.
12 · 12 · 12top of range at 60 kg62.5 kg next sessionAdapt on rough days
Slept badly or feeling run down? Readiness — from HRV, sleep or a 10-second check-in — trims today's session so you still train without digging a hole.
Ready · 96%
5 exercises · 58 min
Full volume, progression available
Recover · 40%
5 exercises · 38 min
Reduced volume, easier day
Built on training logic
Not randomly generated. Progressed by rules.
Fit4i uses consistent progression, volume and periodization rules. The same inputs produce the same programming decision.
AI is used where it helps — estimating meals from food photos. Core training decisions follow deterministic programming logic, not a language model.
Automatic progression
Fit4i knows when to add reps or weight based on your actual performance.
Smart deloads
When fatigue builds up, Fit4i automatically adjusts your training instead of pushing blindly.
Consistent training logic
Your progression follows clear rules instead of random AI-generated workouts.
Workouts built around you — then rebuilt every day.
Your program comes from a training engine grounded in sports science — progressive overload, volume waves and planned deloads — not from a fixed template.
Personalised program
Built from your goal, experience level, equipment and schedule — gym, home dumbbells or bodyweight only.
Automatic progression
Weights, reps and sets advance as you get stronger — no spreadsheet required. Free for everyone.
Short on time?
Tell Fit4i you have 20, 30 or 45 minutes. It compresses rest and trims accessories — your main lift is never touched.
You stay in control
Edit any generated program, build your own from scratch, and swap what you don't like.
One plan. Two different mornings.
- Session
- Day B — Full Body
- Exercises
- 5 exercises
- Duration
- ≈ 58 min
- Volume
- Full volume
- Progression
- Available — weights can move up
Example recommendations from real app states. Your result depends on your data, recent training and check-in — the same percentage doesn't always produce the same decision.
Your plan should adapt when your body does.
The same program is not the right program every day. Fit4i uses your recovery signals to help adjust today's session — so hard days land when you can handle them.
What Fit4i looks at
HRV
vs your personal baseline
Sleep
duration and quality
Resting heart rate
vs your 30-day norm
Blood oxygen
overnight SpO₂
Recent load
days trained without rest
How you feel
a quick morning check-in
Readiness
“Recovery looks strong”
Adjusted workout
Day B — Full Body · 5 exercises · 58 min
Full session — a good day to push progression
Ready — Full session as planned — a good day to push.
Balanced — Session kept, volume trimmed about 25%.
Recover — An easy day — the plan backs off so you can come back stronger.
Know when to push — and when a lighter session makes more sense.
Readiness recommendations are guidance for training decisions, not a medical assessment. Recovery-based adjustments are part of Fit4i Pro; a “feeling unwell” flag always eases the day for everyone.
Know what’s ready to train.
Fit4i tracks recovery across 14 muscle zones based on your logged workouts, so you can quickly see what’s ready and what still needs recovery.
- Just trained
- Recovering
- Ready to train
Based on your logged sets and volume — not a medical measurement.
Training and nutrition in one place.
Daily calorie, protein and fiber targets tied to your goal — and they adapt as your weight trends.
Log a meal from a photo
Snap
Take a photo of your plate.
Recognise
Fit4i identifies the foods and estimates portions and macros.
Review
Check the results and correct anything that's off — nothing is logged blindly.
Done
The meal lands in your diary with calories, protein, carbs, fat and fiber.
Recognised — review before saving
Oats (rolled, dry) · 100 g
kcal
P 12 g · C 62 g · F 7 g — every field editable
- Water tracking with a personal daily target
- Supplement logging — whey, gainer, creatine — with proper serving math
- Body-weight trend that recalculates your calorie target
- Workout history, strength trends and personal records in Progress
Photo recognition produces estimates. Portions and mixed dishes can be hard to judge from a single photo, so you always review and confirm before anything is logged. Photo meal logging is part of Fit4i Pro.
Free to train. Pro to adapt.
Every new account starts with 7 days of Pro — no card required.
Free — forever
- Build and edit your workout program
- Guided logging and full history
- Automatic weight and rep progression
- Fit a session to 20, 30 or 45 minutes
- Calorie, protein and fiber targets
- Water, body weight and supplement tracking
Pro
7 days free- Auto-generated programs from your goal and equipment
- Daily readiness from HRV, sleep and check-ins
- Recovery-driven session adjustments
- Periodized training — volume waves and planned deloads
- Calorie targets that adapt to your weight trend
- Photo meal logging
Pro is an auto-renewable subscription managed through the App Store. Cancel anytime in Settings.
Your data works for you. Nobody else.
Read-only Apple Health access
Fit4i reads sleep, HRV, resting heart rate, blood oxygen, steps and energy — only the types you approve, and it never writes anything back.
No ads, no selling, no cross-app tracking
Your health data is used to adapt your training — never for advertising, and it is never sold.
Food photos are not stored
A photo is analysed to estimate macros and then discarded. It is never saved or linked to your account.
Delete everything, anytime
Delete your account in the app (Settings → Delete account) and your profile, workouts, nutrition and health data are erased.
Frequently asked questions
What is Fit4i?
Fit4i is a gym workout tracker for iPhone. It builds your training program with working weights filled in, handles progression automatically, adapts to your daily recovery and available time, and keeps nutrition tracking in the same app.
Does an AI generate my workouts?
No — core training decisions are deterministic. Progression, weekly volume and periodization are calculated by consistent programming rules, so the same inputs always produce the same programming decision. Fit4i uses AI for food-photo analysis, not for deciding your next weight.
Do I need an Apple Watch?
No. Fit4i reads data any device writes to Apple Health — an Apple Watch works great, but so do many other trackers. Polar devices can connect directly. And with no wearable at all, a 10-second morning check-in (how you slept, how you feel) drives the same adaptive logic.
Does Fit4i work without wearable data?
Yes. The full training engine — program generation, progression, periodization, time-based adjustments — works without any wearable. Readiness then comes from your subjective check-in instead of sensor data.
How accurate is food recognition?
It produces good estimates for common foods, but portions and mixed dishes are genuinely hard to judge from one photo. That's why Fit4i always shows you a review screen first — you check, correct and confirm before anything reaches your diary.
Is my health data private?
Yes. Health data is read with your explicit permission, used only to adapt your training, and never sold or used for advertising. Food photos are analysed and discarded. You can delete your account and all data from inside the app.
Is Fit4i a medical app?
No. Fit4i provides general fitness guidance for healthy adults. It does not diagnose, treat or prevent any condition, and readiness scores are training guidance, not medical assessments. Consult a physician before starting any exercise program.
Stop guessing what today's workout should be.
Open the app. See today's plan. Start training.