A free GLP-1 tracker app for iPhone

Updated September 22, 2026 · WeekArc for iPhone

THE SHORT VERSION

Track injections, weight and body values, protein, fiber, water, daily check-ins and symptoms — on one timeline.
Everything you log is free, forever. No account, no ads, no tracking SDKs.
Your records stay on your iPhone. Apple Health is optional and works type by type.
Arcy, an optional coach that reads your own records, is the one paid part.

What you can track

WeekArc was built for the everyday questions of a GLP-1 journey: when the last shot was, whether this week looks different from the last one, and whether you are eating enough while your appetite is smaller.

Injections. Date, site and your next planned date, with the week at a glance. WeekArc records what you enter — it never suggests, calculates or changes a dose.
Weight and body composition. Weight, waist, estimated fat mass, muscle and lean mass as trends. Values from a smart scale are the scale's own estimates and are labelled "estimated" everywhere they appear.
Protein, fiber and water. Not a calorie counter. No red numbers, no "you went over" warning.
Daily check-in. Hunger, food thoughts, energy and symptoms, recorded as you wrote them and never interpreted.
Visit Summary. A one-page PDF of your own records to take to an appointment.

One timeline instead of four apps

Most trackers do one thing: a shot log, or a scale app, or a food diary. WeekArc puts those records side by side by date, so a week can be read in one place. The Trends tab shows what changed — your progress as a difference between two dates, and your habits as this week against last week.

Eating enough is the real challenge

On GLP-1 medication appetite and energy intake often fall, and a 2025 joint advisory of the American College of Lifestyle Medicine, the American Society for Nutrition, the Obesity Medicine Association and The Obesity Society proposes protein targets of about 1.2–1.6 g per kilogram of body weight per day during active weight reduction, alongside adequate fluids and fiber. WeekArc keeps those three numbers visible instead of a calorie budget. It does not turn a published range into a personal target for you; that conversation belongs to you and your care team. See the sources.

Estimated Medication Timeline

From your own dose records WeekArc draws an educational illustration based on published pharmacokinetic data from the current prescribing information. It is not a measurement, individual responses vary widely, and it never comments on doses. Every figure behind it is linked to its source document.

Which medications it works with

WeekArc records any GLP-1 medication you enter. The medication timeline is shown for medications with published pharmacokinetic data: semaglutide (Ozempic^®, Wegovy^®), tirzepatide (Mounjaro^®, Zepbound^®) and liraglutide (Victoza^®, Saxenda^®). Compounded or custom medications are record-only. WeekArc is not affiliated with Novo Nordisk, Eli Lilly, or any pharmaceutical manufacturer; brand names are used only to identify the medication you recorded.

Private by design

There is no account and nothing to sign up for. The app contains no advertising, analytics or attribution SDKs. Your records live in a database on your iPhone and are part of your own encrypted device backup, so a new phone restores them. Data leaves the device only through something you do: Apple Health permissions you grant type by type, a barcode you scan, a file you export, or the optional Arcy chat you switch on. The privacy policy says exactly what each of those sends.

What it costs

Everything you log is free, forever — doses, weight, meals, water, trends and the Visit Summary. The one optional paid part is Arcy, a coach that reads the records you already keep and talks with you about them: $9.99 per month or $59.99 per year after a 7-day free trial (₺249,99 per month or ₺1.499,99 per year in Türkiye). Arcy coaches habits and consistency, never gives medical advice and never discusses doses.

What WeekArc does not do

It does not recommend, calculate or adjust doses, and it says nothing about a missed dose beyond recording it.
It does not diagnose, treat or interpret symptoms.
It is not a medical device and not a substitute for your prescriber.

Get WeekArc

Download on the App Store

Questions? The frequently asked questions page covers data, Apple Health, the subscription and what Arcy can and cannot do.