Everything DayByDay tracks

GLP-1 Medication Tracking

DayByDay has the most detailed GLP-1 tracker available on the App Store. It's built specifically for the weekly injection cycle of Ozempic, Mounjaro, Wegovy, and other GLP-1 medications.

Supported medications

DayByDay supports all major GLP-1 and dual GIP/GLP-1 receptor agonists: Ozempic (semaglutide), Mounjaro (tirzepatide), Wegovy (semaglutide), Saxenda (liraglutide), Zepbound (tirzepatide), Victoza (liraglutide), Trulicity (dulaglutide), Byetta, and compounded semaglutide or tirzepatide. You can also add any custom medication.

• ✓Live medication level — see exactly how much GLP-1 medication is in your system right now, based on the pharmacokinetic half-life of your specific medication and dose. Tracks peak (24–48 hours post-injection) and trough (just before next dose) automatically.
• ✓Next dose countdown ring — a visual countdown timer shows the hours and minutes until your next injection is due, so you never miss a dose.
• ✓Full injection log — your complete history of every dose: date, medication, dose amount in mg, injection site used, and optional notes.
• ✓Titration timeline — a visual chart of your dose increases over time, so you can track your titration journey from starting dose to maintenance dose.
• ✓Injection site rotation advisor — tracks which body site you used last (abdomen, thigh, upper arm) and recommends where to inject next, reducing the risk of lipohypertrophy from overusing one spot.
• ✓Side effect logging — log nausea, fatigue, GI symptoms, or any other side effects by date, so you can share them with your prescribing provider.
• ✓Multi-medication support — if you take more than one injectable medication, DayByDay can track them simultaneously.
• ✓Dose override — if your provider adjusts your schedule or you inject early or late, you can manually override the next dose date and time.

Weight Tracking

Weight loss is not a straight line. Daily weight fluctuates by 1–4 lbs due to water retention, meals, hormones, and other factors. DayByDay cuts through the noise with a smoothed trend line that shows your real progress.

• ✓Smoothed trend line — an exponential moving average shows your true trajectory, separate from daily noise. See your real rate of loss even on days when the scale goes up.
• ✓Multi-layer chart — view raw daily weigh-ins, the smoothed trend, and weekly highs/lows all in one chart, with date range selector (7 days to all time).
• ✓Body fat percentage tracking — log and trend body fat % over time, calculated from any method (scale, DEXA, tape measure, etc.).
• ✓Lean mass estimates — automatically calculates lean body mass in lbs or kg based on your weight and body fat percentage, so you can see if you're losing fat vs. muscle.
• ✓BMR (basal metabolic rate) — estimates how many calories your body burns at rest, updating as your weight changes. Based on the Mifflin-St Jeor equation.
• ✓Metabolic age — compares your estimated BMR to the average BMR for different ages, giving you a metabolic age estimate.
• ✓BMI tracking — automatic BMI calculation and trend as your weight changes, with standard BMI category indicators.
• ✓Goal date predictions — based on your actual smoothed rate of loss, DayByDay predicts when you'll reach your goal weight, with an optimistic and conservative range.
• ✓Upcoming milestones with dates — see your next upcoming milestones (next 5 lbs, next 10 lbs, 5% of starting weight, 10% of starting weight, goal weight) with estimated dates based on your current rate.
• ✓Weekly stats — weekly high, low, average, and net change (vs. prior week) auto-calculated.
• ✓lbs and kg support — switch between pounds and kilograms at any time. Stone display also supported.
• ✓Apple Health sync — imports weight measurements from Apple Health automatically, including data from smart scales (Withings, Renpho, etc.) that write to Apple Health.
• ✓CSV weight history import — upload a CSV file of past weight data via app.mydaybyday.app to see your full history from day one.
• ✓Manual entry protection — manually entered weights are never overwritten by Apple Health syncs.

Sleep Tracking

Sleep quality has a direct impact on weight loss, appetite regulation, and GLP-1 medication effectiveness. DayByDay gives you the most detailed sleep analysis of any weight loss app.

• ✓Sleep stages breakdown — total time in awake, REM, core (light), and deep sleep, shown as time and percentage, with a visual donut chart for each night.
• ✓Blood oxygen (SpO2) tracking — nightly average SpO2, minimum SpO2, oxygen dip count per hour, and an overall O2 score. Useful for identifying sleep apnea patterns.
• ✓Blood oxygen trend chart — view your overnight SpO2 levels plotted as a continuous chart, so you can see dips and their timing.
• ✓Sleep debt tracker — tracks cumulative sleep debt across the week and provides personalized recovery tips based on how much sleep you've missed.
• ✓Overnight heart rate — average resting heart rate while asleep, trended over time.
• ✓Respiratory rate — average overnight breaths per minute, useful as an early indicator of illness or sleep apnea changes.
• ✓Feel refreshed rating — log how refreshed you felt on waking (1–5 scale) to capture subjective sleep quality beyond the numbers.
• ✓Sleep quality correlation — see how your sleep score correlates with your weight trend over time.
• ✓Apple Health sync — pulls sleep stages and overnight vitals from Apple Watch and any Apple Health–compatible sleep tracker automatically.
• ✓O2 Ring support — imports detailed overnight oxygen data from Wellue/Viatom O2 Ring devices via CSV export, for users without an Apple Watch.

Body Measurements & Lab Results

The scale doesn't tell the whole story. DayByDay tracks inches lost, body composition metrics, clothing sizes, and lab values that matter for metabolic health.

Body measurements

• ✓Waist, chest, neck, and hips — log in inches or centimeters with trend charts for each measurement over time.
• ✓Clothing size tracker — log shirt size, pant size (waist + inseam), and dress size. See the history of your size changes as you lose weight.
• ✓Waist-to-height ratio (WHtR) — a more reliable health indicator than BMI. Values under 0.5 are associated with reduced cardiometabolic risk.
• ✓Relative fat mass (RFM) — a body fat estimate based on waist and height measurements, without requiring a scale or body fat scale.
• ✓Fat-free mass index (FFMI) — tracks changes in muscle mass relative to height.

Lab results

• ✓Hemoglobin A1c — log A1c results and view a trend chart over time. Critical for people with type 2 diabetes or prediabetes on GLP-1 medications.
• ✓Fasting glucose — track fasting blood sugar readings from lab work.
• ✓Cholesterol panel — total cholesterol, LDL, HDL, and triglycerides.
• ✓Full lab history — every lab result with date, so you can see how your numbers improve over the course of your weight loss journey.

Exercise & Activity

DayByDay pulls activity data from Apple Health automatically — no manual logging required. See how your fitness level improves as you lose weight.

• ✓Daily steps — synced from Apple Health (iPhone, Apple Watch, or any step-counting device) with trend chart.
• ✓Active calories — calories burned through physical activity (above resting metabolism), synced from Apple Health.
• ✓Exercise minutes — total daily active minutes from Apple Health workouts.
• ✓Resting heart rate — a key indicator of improving cardiovascular fitness as you lose weight. Trended over weeks and months.
• ✓Activity trend charts — weekly and monthly views of steps and exercise minutes, so you can see your consistency improving.
• ✓Active day streaks — tracks consecutive days where you hit a step or exercise goal, encouraging consistency.
• ✓Total daily energy expenditure (TDEE) — estimates your total daily calorie burn (BMR + active calories) to help you understand your overall energy balance.

Dashboard

The DayByDay dashboard is your daily check-in — a single screen that gives you everything you need to know at a glance, without overwhelming you with numbers.

• ✓Goal progress — how much you've lost, how far to your goal, and your percentage complete — always visible at the top.
• ✓Today's Pulse — a daily snapshot card: sleep quality last night, medication status (how many hours until next dose), step count, and exercise status.
• ✓Momentum streak — your consecutive check-in days, displayed with a visual streak badge. Encourages daily habit formation.
• ✓Coach Notes — personalized, data-driven insights written in plain language: "You're losing 2.3 lbs/week on average — faster than your target", "Your deep sleep improved 18% this week", "Your A1c dropped 0.4 points since starting Ozempic."
• ✓Customizable card layout — drag cards to reorder the dashboard to show what matters most to you at the top.
• ✓Journey Mode — a beautiful sunset-themed dark interface option that makes checking in feel like a reward, not a chore. Switches automatically at dusk or can be enabled manually.

Smart Features

• ✓Milestone celebrations — hit 5 lbs, 10 lbs, 10% body weight, or your goal weight and get a confetti animation and personal recognition message. You earned it.
• ✓Goal date predictions — calculated from your actual smoothed rate of loss, not a fixed formula. Updates automatically as your rate changes.
• ✓Data correlation insights — DayByDay surfaces connections between your tracked variables, such as how your sleep quality correlates with your weight trend.
• ✓Apple Health sync (full) — weight, body fat %, sleep stages and vitals, step count, active calories, exercise minutes, resting heart rate. All synced automatically when you open the app.
• ✓Offline support — log weight, doses, sleep, and measurements even without an internet connection. Data syncs to the cloud when you're back online.
• ✓Doctor-ready exports — export any dataset as a PDF or CSV to share with your prescribing provider, endocrinologist, or nutritionist. Weight chart, GLP-1 history, lab trends — all exportable.
• ✓Dark mode — follows your system preference, with a stunning deep blue-navy dark theme designed to be easy on the eyes at night.
• ✓lbs, kg, and stone — full unit support for weight. Measurements in inches or centimeters.

Privacy & Trust

Your health data is personal. DayByDay is built around the principle that your data belongs to you — not to advertisers, not to data brokers.

• ✓No ads, ever — DayByDay is a subscription app. Your data is never used for advertising and never sold to third parties.
• ✓Encrypted at rest — all health data is encrypted in the database.
• ✓Delete everything anytime — a single "Delete All My Data" button in settings permanently removes all your data from DayByDay's servers. No support ticket required.
• ✓No food logging — DayByDay doesn't track what you eat, so there's no calorie diary that could become a source of diet culture pressure or disordered eating.
• ✓Great companion app — DayByDay pairs with your existing food tracker (MyFitnessPal, Lose It!, MacroFactor, Cronometer) rather than replacing it.

Frequently Asked Questions