Body & Composition
Trending right
You're at 26.1% body fat and 221.9 lbs. More importantly: you've gained muscle while losing fat. That's the kind of loss that lasts.
The last GLP‑1 tracker you'll need
Everything that moves your weight, in one app.
Nutrition and macros, GLP‑1 doses, weight, sleep, and labs — tracked together and tied to a daily AI coach that connects what you eat to how you feel. Track what matters. Build a healthier you — day by day.
4.8 · loved by GLP‑1 patients
Built for your whole journey
Lose Weight
Eat with Intention
Keep Your Muscle
Feel Your Best
New in v3 · Nutrition
Start tracking nutrition →
Log your food in seconds. Understand it for life.
A full calorie & macro tracker built for GLP‑1 life — where protein and fiber matter as much as calories. Snap, scan, or search. We do the math; the coach does the meaning.
Search
Millions of foods, brands & restaurants.
Scan barcode
Point at packaged foods — macros fill in.
Photo of plate
AI estimates the whole meal at once.
Nutrition label
Read the panel; we parse the rest.
No signal? Snap it anyway.
Basement restaurant, airplane, trailhead — DayByDay saves your photo on the spot, logs it the moment you're back online, and taps you on the shoulder when it's done.
Food database powered by FatSecret
Insights · Meet Dayo, your AI coach
A coach who reads your week and tells the real story.
Powered by Anthropic Claude, Dayo reads your weight, body composition, doses, sleep, and nutrition — then writes your Insights tab fresh every day: a warm opening read and four Story Cards. Candid, like a friend who's been through the GLP‑1 journey themselves.
- Four daily Story Cards — Body, Pace, Fuel & Sleep — plus a weekly Your Story
- Connects food to outcomes — protein vs. muscle, fiber vs. side effects
- Phase- and medication-aware: loss, maintenance, and the comeback
- Every claim backed by a real fact from your data — tap to see the evidence
- Plateau Watch spots a stall early and shows you why
Monday, Jun 15 · This week's read
Your body is reshaping—
lean mass up, fat down.
🏋️ Body
📉 Pace
🍎 Fuel
🌙 Sleep
Your sleep's solid and you're burning fat while building muscle — that's the goal. Log a few meals today and tomorrow so we can dial in whether you need to bump your protein; hydration's light and can make nausea worse on semaglutide.
Weight-Loss Pace
Looking good
Dropping about 1.1 lbs a week — a solid, healthy pace. The scale's moving in the right direction, and the composition tells the real story.
Fuel & Protein
Worth a look
Protein landed at 0.6 g/lb on average — a little under target for holding muscle through the deficit. One more protein-forward meal a day closes the gap.
Sleep & Energy
Looking good
Five solid nights in a row — your sleep debt is nearly paid off, and tomorrow's energy peak lands around 9:40 AM. Good morning to book the hard stuff.
Dayo · powered by Anthropic
Next read · tomorrow 8:00 AM
Dayo is your companion, not a doctor — check with your care provider before changing your medication, diet, or routine.
Follow along
Your journey, one ordinary day at a time.
This is DayByDay the way you'll actually live with it—a single, unremarkable day that quietly adds up to a whole transformation. Tap a chapter, or just follow along.
7:04 AM. You're barely awake.
One glance, and you know you're okay.
Before coffee, before the day gets loud, DayByDay hands you the headline—and most mornings, you're doing better than it feels.
Momentum Score
A single 0–100 read on how your whole week is trending.
Today's Pulse & streaks
Sleep, protein, hydration and activity at a glance, plus your check-in and dose streaks.
Make it yours
Reorder and hide cards so Today shows only what you care about, with two-tap Quick Add.
Mid-morning. A hundred little things.
Log life as it actually happens.
A glass of water. Today's weigh-in. That twinge of nausea after your shot. If it matters to your body it goes down in two taps—and it all feeds one picture, because it's all connected.
Body & composition
Weight, body measurements, DEXA scans and clothing sizes.
Intake
Water, medication doses, and the full nutrition module.
How you feel
Mood, GLP‑1 symptoms, blood glucose and blood pressure—so patterns surface.
12:40 PM. Lunch in a basement diner.
Snap your plate—even with one bar.
A sandwich you couldn't name if you tried, and no signal to look it up. You take the photo anyway; DayByDay logs it the moment you're back above ground. Nothing lost, nothing to redo.
Four ways to log
Search millions of foods, scan a barcode, snap your plate, or read a nutrition label.
Protein & fiber first
The macros that protect muscle and ease side effects, kept front and center.
Snap now, log later
No signal? DayByDay saves the photo and logs it automatically the moment you reconnect.
Sunday. You step on the scale.
The scale lied. Your trend told the truth.
Up a pound today—but the smoothed line is still falling. DayByDay shows you the real slope under the daily noise, and roughly when you'll reach your number.
Smoothed trend line
Raw weigh-ins, a smoothed line, and weekly highs and lows in one clear chart.
Goal projection
A next-month estimate and goal date, drawn from your actual rate of change.
Body composition
Body-fat %, lean mass, BMR, RFM and FFMI—with a warning if a GLP‑1 takes muscle.
Dose day. Tuesday, 8 AM.
Never guess where you are on your meds.
Which site this week? How much is still working? When's the refill? It's all right here—so the medication feels less like a mystery and more like a plan you're in control of.
Live medication level
See how much is active right now, plus a visual next-dose countdown ring.
Titration & rotation
Dose history, stall detection, and an injection-site rotation advisor.
Pharmacy & refills
Next pickup, prior-auth tracking and reminders, so you never run out mid-titration.
That night, and the morning after.
Sleep in. Wake to a plan for your energy.
DayByDay reads last night—stages, oxygen, overnight vitals—and forecasts today: when you'll peak, when you'll crash, and when to finally put the coffee down.
Sleep, decoded
REM, deep and core stages, blood-oxygen dips, heart rate and HRV.
Energy Schedule
A 0–100 forecast of your peaks and afternoon dip, rebuilt every night.
Time it right
A caffeine cutoff and ideal bedtime window, drawn from real sleep science.
Sunday evening. The check-in you look forward to.
A coach who actually read your week.
Not generic tips. Powered by Anthropic Claude, Dayo ties your protein to your muscle and your sleep to your mood—candid and warm, like a friend who's been through it themselves.
Daily read + Story Cards
A warm daily opener plus four cards: Body, Pace, Fuel and Sleep.
Backed by your data
Every claim ties to a real number from your logs—tap to see the evidence.
Plateau Watch
Spots a stall early and shows you exactly why it's happening.
Any time you open the app.
Two ways to see the very same day.
Some days you want the reward: a living interface that shifts from dawn to dusk, quietly mirroring the transformation you're living. Other days you just want the numbers. One tap swaps between them.
Journey Mode
The full experience—a beautiful interface that changes through the day, a mirror for the transformation your body's living.
Focus Mode
Prefer it plain? Focus Mode strips the styling away, leaving a calm, distraction-free view of just what matters.
Light & dark
Whichever mode you choose, it follows your system's light or dark theme automatically.
In line at the pharmacy. A glance at your wrist.
The number you need, before you unlock.
Next dose in two days. Energy at 84. It's already on your Lock Screen, in the Dynamic Island, and on your watch—no app to open, no digging required.
Dynamic Island
A live dose countdown and energy potential, right at the top of your screen.
Lock Screen widgets
Weight trend, energy and next dose as glanceable widgets you can tap.
Home Screen complications
Home Screen and Apple Watch complications keep your day one tap away.
The morning of your appointment.
Walk in ready. Walk out reassured.
One tap turns months of data into a clean PDF your doctor can actually use. And every byte stays yours—encrypted, private, and gone the second you decide it should be.
Health Report PDF
Charts, flagged insights and your medication summary, ready to share.
Export everything
A CSV of every table—weight, doses, sleep, labs, nutrition and more.
Private by design
Encrypted at rest, row-level security, no ads, and delete-it-all in one tap.
Next dose · 2d
9:41
Monday, July 6
2d
Next doseTue · 8:00 AM · Semaglutide
That's the whole day. Ten minutes to set up—then it just quietly has your back, day by day.
Download Free → Free to start · no credit card · iPhone & Android beta
GLP‑1 HUB
Finally understand your GLP‑1 journey.
Track your medication, doses, side effects, and results in one place — with guidance for every step, from titration to refills.
- Live medication level & next-dose countdown
- Side effect & symptom tracking
- Dose history, titration analysis & stall detection
- Injection-site rotation advisor
- Pharmacy & Refill Hub with prior-auth tracking
Medication Level
49%
1.7mg
Brand Semaglutide
49% of full effectiveness · Week 37
Next Dose
Tue · 8:00 AM
On schedule
Rotation Advisor
Right Thigh next
4 of 6 zones used
Next Pickup
PA active
in 27days
Ready Jun 11 · CVS #4920
Sleep & Recovery
Better sleep.
Better you.
Track sleep stages, recovery, HRV, and overnight oxygen to understand your body — then watch last night become tomorrow's energy forecast.
- Sleep stages & Sleep Score
- HRV & Resilience Score
- Blood oxygen & overnight vitals
- Sleep debt & your Energy Schedule
One tab to log it all
Your whole day,
one tap each.
Food, water, weight, medication, activity, sleep, mood, blood pressure, glucose, and symptoms — all in the Track tab. Tap to log, long-press for history.
- Quick-add tiles on the Today screen
- Blood pressure, glucose & mood logging
- Apple Health & O2 Ring sync
- Works offline — syncs when you're back
New in v3 · Energy Schedule
Know your day before it starts.
Last night's sleep writes today's story. DayByDay turns your sleep rhythm and sleep debt into a personal energy forecast — so you plan the hard things for your peak, ride out the dip guilt-free, and wind down right on time.
- A live energy potential (0–100) that follows your body clock
- Morning peak, afternoon dip & evening rebound — mapped to real times
- Caffeine cutoff, wind-down & ideal bedtime, recomputed every night
- Right on your Lock Screen & Dynamic Island, all day long
Built for the whole arc
Loss is just chapter one.
Most apps quit when you hit goal. DayByDay changes with you — through maintenance and the comeback.
1
Phase 1 · Loss
62% to goal · 40.7 lbs down
Get there with clarity.
Smoothed trends, projected goal dates with confidence bands, body-fat % projections, milestone celebrations, and a coach that respects your titration step.
2
Phase 2 · Maintenance
77-day streak · held steady at 225 lbs
Hold the line, calmly.
A Maintenance Range card replaces Goal Progress. Track drift from goal, in-range streaks, 30-day variability, and maintenance milestones at 30, 90, 180, 365, and 730 days.
3
Phase 3 · Comeback
+1 lb · body fat ↓ 0.3%
A comeback, not a setback.
If weight drifts back above your maintenance band, the app gently flags it and the AI coach shifts to comeback-oriented guidance. No shame. Just the data and a path forward.
For your appointments
Bring your provider the full picture.
Your appointment is fifteen minutes. Your journey is twenty-four seven. Walk in with a doctor-ready report of everything that happened in between — so the person prescribing your medication has the details they need to help you decide what's next.
Doctor-ready PDF & CSV exports
Weight trend, body composition, dose history, side effects, labs, and sleep — clean, timestamped, and printable in two taps.
The story between visits
Titration steps next to your weight response. Side effects next to dose changes. The patterns your provider never gets to see — until now.
Labs in context
A1c, glucose, lipids, and blood pressure charted against your weight and doses — proof of progress that goes beyond the scale.
Privacy-first
Your health data, yours alone.
Row-level security
Every database table is scoped to your account. No human reviews your data without your permission.
Encrypted at rest
Your data is encrypted on disk. Progress photos live in a private, encrypted bucket — local-first by default.
No ads, ever
Your data is never sold or used for advertising. No social feed. No leaderboards.
One-tap delete
Delete everything anytime. Full control over your data, always.
DayByDay Plus
On a GLP‑1? Plus is how you keep the muscle.
Losing weight is the easy part — losing it without losing muscle is the whole game. Plus logs your food in seconds and coaches every bite toward your goal.
Core
Shows your trends and tells you what happened.
Plus
Logs your food in seconds and tells you what to do next.
Logging in seconds
Snap a photo of your plate, scan a barcode, or search millions of foods. Favorites, recents, and copy-from-yesterday make tomorrow even faster.
Muscle-first coaching
Protein, fiber, and hydration targets tuned to your weight, goal, and dose. Plus flags low protein before it costs you muscle — and low fiber before it costs you a rough day.
Food connected to outcomes
The enhanced AI coach links what you eat to how you progress — protein vs. loss rate, fiber vs. side effects — and turns it into a forward-looking weekly plan, not just a recap.
Your GLP‑1 costs hundreds a month. Plus is about 33¢ a day — to protect that investment, and the muscle you're working to keep.
Pricing
Start free. Upgrade when you're ready.
Logging is free forever. Core unlocks the analysis layer. But the full DayByDay is Plus — nutrition, AI coaching that connects food to your outcomes, and your daily Energy Schedule.
Free
$0 /forever
Log everything, no time limit, no credit card.
- All logging — weight, doses, sleep, exercise, labs
- Track tab: water, mood, blood pressure, glucose
- Full history & your data, always exportable
- No ads. Your data is never sold.
Core
$4.99 /mo
$49.99 /yr
About 16¢ a day. Billed monthly.
$49.99 billed yearly · about 14¢ a day.
- Trends, smoothing & goal projections
- Dayo AI Coach — daily read & weekly Story
- GLP‑1 Hub, Pharmacy & Refill tracking
- Sleep Score, Resilience Score, glucose trends
- Journey Mode, milestones & streaks
- Apple Health sync & doctor-ready PDF export
Most popular
Plus Nutrition + AI
$9.99 /mo
$99.99 /yr
About 33¢ a day · just $5 more than Core.
$99.99 billed yearly · about 27¢ a day.
Everything in Core
The upgrade that protects your muscle and your meds — effortless logging plus a coach that turns every meal into a next step.
- Nutrition tab — calories, protein & fiber rings
- FatSecret search, barcode scan & photo-of-plate — even offline
- Favorites, recents & copy-from-yesterday
- Enhanced AI — food↔outcome coaching
- Energy Schedule — your daily energy forecast
- Protein, fiber & hydration targets tuned to your dose
Free for your first 14 days — then you keep the Free plan unless you subscribe.
Every new account starts with 14 days of full Plus, free — no credit card. If you don't subscribe, you simply keep the Free plan. Cancel anytime — your data is always yours.
Nutrition food database powered by FatSecret
Questions
Things people ask before downloading.
How does DayByDay track nutrition and macros?
The Nutrition tab (DayByDay Plus) is powered by FatSecret. Log food four ways:
search a database of millions of foods, scan a barcode, snap a photo of your plate for AI
portion estimates, or read a nutrition label. Calories, protein, and fiber are the
highlighted metrics — with carbs and fat tracked too. Tap a result to log a serving as-is;
long-press to adjust the portion first.
Does food logging work without a connection?
Yes. Snap a plate photo, scan a barcode, or capture a nutrition label with a bad
connection, and DayByDay saves it on your phone as "Waiting for connection."
The moment you're back online it processes automatically, logs the food to your day,
and sends you a "Your food is logged" notification. Nothing is lost —
and there's nothing to redo.
What is the Energy Schedule?
A personal daily energy forecast (DayByDay Plus) built from your real sleep rhythm and
sleep debt, using the two-process model from sleep science. It predicts your
energy potential (0–100) across the day — morning peak, afternoon dip,
evening peak, and wind-down — plus a caffeine cutoff and an ideal bedtime window,
recomputed every night. You can pin it to your Lock Screen and Dynamic Island.
What does the AI coach actually do?
Dayo (powered by Anthropic Claude) reads your real data — weight, body composition, GLP‑1
doses, sleep, and nutrition — and writes a plain-language daily read plus a weekly Your
Story. On Plus it connects food to outcomes: protein vs. muscle retention, fiber vs. GI
side effects, energy balance vs. your weight trend. Every claim is backed by a real fact from
your own data. Dayo is a companion, not a doctor.
What's the difference between Free, Core, and Plus?
Free lets you log everything, with no time limit. Core
($4.99/mo or $49.99/yr) adds the analysis layer: trends, projections, the AI coach, Journey Mode,
health sync, and exports. Plus ($9.99/mo or $99.99/yr) adds the full Nutrition
module (FatSecret search, barcode, photo-of-plate — even offline), the Energy Schedule
forecast, and the enhanced AI coach that connects nutrition to your weight and muscle
outcomes. Every new account also starts with a 14-day free trial of the full Plus experience
— no credit card — and drops back to Free afterward if you don't subscribe.
I'm an existing Premium subscriber — what happens to me?
You're grandfathered in. Existing Premium subscribers keep everything they have today at their
current price, mapped to the new Core tier. Nutrition and the enhanced coach
live in Plus — available any time as an upgrade, never a forced migration.
Is DayByDay for Ozempic, Mounjaro, Wegovy, or Zepbound users?
Yes. DayByDay supports every major GLP‑1 medication: Ozempic, Wegovy, Mounjaro, Zepbound,
Saxenda, Victoza, Trulicity, Rybelsus (oral semaglutide), and compounded semaglutide or
tirzepatide. The app tracks dose level, titration history, injection sites, pen storage,
refills, and prior-authorization renewals.
What happens after I reach my goal weight?
DayByDay switches into maintenance mode. The Goal Progress card becomes a
Maintenance Range card tracking drift from goal, in-range streaks, and days at goal. If weight
drifts back up, the app gently flags it and the coach shifts to support a comeback, not lecture
you.
Is my health data private?
Yes. Every database table has row-level security scoped to your account. Data is encrypted at
rest. There are no ads, ever. Your data is never sold or used for advertising. You can delete
everything with one tap.
Does it work with Apple Watch or the Wellue O2 Ring?
Yes. DayByDay syncs weight, sleep stages, steps, active calories, heart rate, HRV, VO2 max,
blood oxygen, and body temperature from Apple Health. The O2 Ring (Wellue / Viatom) can be
imported separately for detailed overnight oxygen data.
Is there an Android version?
Yes — DayByDay for Android is in open beta on Google Play, with Health Connect sync built in.
You can join the beta and start using it today; tap the Google Play button above. The full
Android release is on the way. The iPhone app is live on the App Store.
Tomorrow's progress starts today.
One small entry. One better meal. One more step forward.