Welcome to DayByDay
DayByDay is a weight loss and wellness tracking app — not a food diary, not a calorie counter. You log your weigh-ins, medications, sleep, exercise, and measurements, and DayByDay turns that data into real, actionable insights.
The philosophy is simple: track your outcomes, not your inputs. DayByDay works great alongside your favorite food tracker (like MyFitnessPal or MacroFactor) — it just handles the other half of the picture.
Not a medical device
DayByDay is a personal tracking tool, not a medical device. The data you see is for your own awareness and motivation. It is not a substitute for advice from your doctor, dietitian, or any other healthcare provider.
Step 1 — Set your goal weight
The first time you open the app, onboarding will ask for your current weight, your goal weight, and which unit you prefer (lbs or kg). You can change any of these later in Settings → Profile.
- 1Open DayByDay and complete the onboarding screens.
- 2Enter your current weight and your goal weight.
- 3Choose lbs or kg — DayByDay converts automatically if you ever switch.
- 4Optionally connect Apple Health so your data syncs automatically.
Step 2 — Log your first weigh-in
Tap the Weight tab, then hit the + button in the top right. Enter your weight and hit Save. That's it — your first data point is in.
Best time to weigh in
Weigh yourself first thing in the morning, after using the bathroom and before eating or drinking. Doing it at the same time each day gives you the most consistent readings.
Step 3 — Connect Apple Health (optional but recommended)
If you're on iPhone, connecting Apple Health is the easiest way to get your data into DayByDay without any manual entry. Weight, steps, sleep, and workouts all sync automatically.
Go to Settings → Health sync and tap Connect Apple Health. You'll see a permissions sheet — turn on everything you want DayByDay to read.
A quick tour of the 6 tabs
- ✦Dashboard — Your daily summary: streak, goal progress, Coach Notes, and Today's Pulse.
- ✦Weight — Log weigh-ins, view your trend chart, and track body fat percentage.
- ✦GLP-1 — Track your medication doses, injection sites, and see your medication level in real time.
- ✦Sleep — Sleep stages, blood oxygen, overnight vitals, and your O2 Score.
- ✦Exercise — Steps, active calories, exercise minutes, and resting heart rate.
- ✦Measurements — Body measurements, clothing sizes, and lab results like A1c and cholesterol.
Your free trial
Every new account gets a 14-day free trial with full access to every feature — no credit card required to start. After the trial, DayByDay is $5.99/month or $59.99/year (save 17%).
Premium — Full access, free for 14 days
Try every feature — trend charts, GLP-1 tracking, blood oxygen analysis, and Coach Notes — with no commitment. Upgrade or cancel anytime.
Frequently asked questions
Can I import my weight history from another app?✦
Yes. You can upload a CSV file at web.mydaybyday.app. See the Importing CSV files article for the exact format.
Does DayByDay count calories or macros?✦
No, and that's intentional. DayByDay tracks outcomes — your weight trend, sleep quality, activity levels, and medication adherence. Pair it with your favorite food tracker if you want to log meals.
Is my data private?✦
Your health data is encrypted at rest and is never sold or used for advertising. You can delete everything at any time from Settings → Account → Delete my data.