How to Create a Fitness Coaching App (2026)
Create a fitness coaching app for your clients: training plans, logging, progress charts, check-ins and coach messages, built natively with Borel.
By Sigsten Gustavii· · 9 min read
To create a fitness coaching app, decide what your clients do between sessions, describe the client and coach screens to an AI builder like Borel, test a full week of a plan on a live iPhone, then give the app to a few clients before you publish it under your own name.
| Who | What they do in the app | What it replaces |
|---|---|---|
| Client | Sees today's workout, logs sets, ticks off habits, sends a weekly check-in | Spreadsheets, PDFs and screenshots in a chat app |
| Coach | Writes plans, reviews logs and check-ins, replies to messages | A folder per client and late-night messages |
| Both | See progress on charts over weeks | Guessing whether it is working |
Most trainers run their coaching on a messy mix of spreadsheets, PDFs and messages. A coaching app puts the plan, the log and the conversation in one place with your name on it. It is not a workout tracker for the whole world; it is a tool for you and your clients, which is exactly the kind of app an AI builder makes well.
If you only want to log your own training, a simpler workout log app is the place to start. This guide is about coaching other people.
What a fitness coaching app needs
| Part | What it does | How Borel builds it |
|---|---|---|
| Client profiles | Goals, level, injuries to work around | Profiles in Borel Cloud that only the client and their coach read |
| Plans | Weeks of workouts with exercises, sets, reps and rest | Plans the coach writes and assigns to a client |
| Workout player | Today's session, one exercise at a time, with a rest timer | A native SwiftUI screen with timers and haptics |
| Logging | Weights and reps, how it felt | Logs saved to the client's account |
| Progress | Lifts, body weight, steps over time | Swift Charts drawn from the logs |
| Check-ins | Weekly answers and progress photos | A form with photos in private file storage |
| Messages | Questions between sessions | Conversations only the client and coach can read |
Everything lives in Borel Cloud, the database, sign-in and file storage Borel runs. Each table has an access rule, so a client's progress photos are readable by that client and their coach and nobody else.
What a coaching app can measure on an iPhone
Be clear about data before you promise it to clients:
- What clients type in: weights, reps, how a session felt, body weight, sleep hours, meals. This is most of coaching.
- Steps and activity counted by the iPhone's own motion sensors through Apple's Core Motion. See motion and steps.
- Photos from the camera or the library, for check-ins and form checks.
- Not Apple Health or Apple Watch. Borel apps don't read heart rate, workouts or sleep from Apple Health, and there is no Apple Watch app. If your coaching depends on wearable data, plan for clients to type the numbers in.
Make the workout screen feel good
Clients spend most of their time in the workout player, often sweaty and out of breath. Design it for that:
- One exercise per screen, big type, the next set clearly marked.
- A rest timer that starts by itself after a set and buzzes with a haptic when rest is over.
- Last time's numbers next to this time's, so progress is obvious.
- Large buttons that work with chalky fingers.
- It works offline, because gyms are often in basements. Ask for today's plan to be kept on the phone; see offline data.
Progress charts and check-ins
Progress keeps clients paying. Ask for charts of the numbers that matter for each goal: estimated one-rep max for strength, weekly volume, body weight as a seven-day average, or daily steps. Apple's Swift Charts draws them natively, in light and dark mode.
A weekly check-in is the other half: five short questions (energy, sleep, stress, hunger, wins), body weight and optional photos from the photo library. The coach sees a list of new check-ins and replies in the conversation.
What to build in version one
Coaches tend to ask for everything at once: nutrition tracking, a recipe library, group challenges, a community feed. Start with the loop your clients repeat every week and add the rest once they use it:
| Build now | Add later |
|---|---|
| Today's workout and logging | Group challenges and leaderboards |
| Progress charts for two or three numbers | Meal plans and a recipe library |
| Weekly check-in with photos | A community feed between clients |
| Private coach messages | An AI assistant that drafts replies |
Each item in the right column is a message or two later, once you know your clients want it.
How coaches get paid under Apple's rules
This is where coaching apps get confused, so it is worth reading Apple's own App Review Guidelines:
| What you sell | Apple's rule | How to charge |
|---|---|---|
| Training plans or a library in the app | 3.1.1: digital content uses in-app purchase | A subscription or one-time purchase through Apple, built by Borel |
| Live one-to-one coaching between two people | 3.1.3(d): real-time person-to-person services may use other methods | Your existing invoicing or payment link |
| In-person sessions at a gym | Services outside the app | As you do today |
For plans sold in the app, use the Add payment button in Borel: set the plan's name, billing cycle and price, and Borel builds the paywall on Apple's StoreKit with Restore Purchases and creates the product at Apple when you publish. See in-app purchases. Apple keeps 15% under its Small Business Program for developers earning up to $1 million a year.
App Store rules for fitness apps
| Guideline | What Apple asks | What to do |
|---|---|---|
| 1.4.1 Medical apps | Apps that could give inaccurate health information get greater scrutiny | Coach training, not treatment; say so in the app |
| 3.1.1 In-app purchase | Digital plans unlocked in the app use in-app purchase | Use Borel's Add payment |
| 5.1.1(v) Account deletion | Delete account in the app | Built into every Borel app with accounts |
| 5.1.1(i) Privacy policy | A link in the app and on the listing | Borel hosts one and links it |
| 2.1 Completeness | A demo account for apps with a login | A client account with a plan and logs, and a coach account |
What a coaching app costs
| Item | Cost | Notes |
|---|---|---|
| Borel Free | $0 | 5 credits a day to build and try it in your browser |
| Borel Pro | From $20 a month | Install on phones with Companion and publish to the App Store |
| Apple Developer Program | $99 a year | Paid to Apple; you are the seller on the App Store |
| Running the app | Pay as you go | Logs, photos and messages, from a balance you top up |
That is $339 a year on Borel's lowest monthly tier plus Apple's fee, about what one or two clients pay you in a month. See pricing.
How to choose the right coaching app builder
- Borel, for your own branded native iPhone app with plans, logging, charts, check-ins and messages, built from a description.
- [CatDoes](/compare/catdoes), if many of your clients use Android; it builds React Native apps for both stores.
- A coaching platform, if you want a ready-made system with Android, wearables and payments, and accept their branding and monthly fee per client.
- A spreadsheet and a chat app, if you have three clients and no plans to grow.
How to do it with Borel, step by step
Step 1: Write down your method
List your plan format (weeks, days, exercises, sets, reps, rest), your check-in questions and the numbers you track. That is your app.
Step 2: Describe the app
Make a coaching app for my strength clients. Clients sign in with email and see today's workout from the plan I assigned: one exercise per screen with sets, reps and target weight, last session's numbers beside it, and a rest timer that starts after each set and buzzes when done. They log weight and reps and rate the session 1 to 5. Charts show estimated one-rep max per lift and body weight as a 7-day average. Every Sunday they answer five check-in questions and can add photos. I sign in as the coach, write plans from an exercise library, assign them to clients, see new logs and check-ins, and message each client privately. Keep today's workout on the phone so it works offline.Borel's planner, Penny, asks about anything unclear, then Rivet writes the app in Swift with SwiftUI and Xcode compiles it on Borel's Mac.
Step 3: Run a week on a live iPhone
In the iOS Simulator in your browser, make a coach and a client account. Assign a plan, log three workouts, send a check-in and reply to it. Ask for changes in plain words until the workout screen feels quick.
Step 4: Train with it
With Pro, Borel Companion installs the app on your iPhone from a Windows PC or a Mac, so you can feel the haptics and test steps. Use it for your own training for a week, then give it to three clients through TestFlight.
Step 5: Publish
Stamp checks the app for the rules Apple most often turns apps down for, and Publish builds, signs and uploads it under your own Apple Developer account.
The Bottom Line
A coaching app turns your method into something clients carry in their pocket. With Borel, the plans, workout player, logs, charts, check-ins and messages come from one description, natively on iPhone and under your own name. Be honest with clients that it doesn't read Apple Health, sell digital plans through Apple, and keep live coaching on your own invoices. Describe your method on Borel and log a workout on a live iPhone today.
Questions people ask
Can a personal trainer make their own app?
Yes. With Borel you describe your plans, check-ins and the screens your clients need, and it builds a native iPhone app you publish under your own Apple Developer account. No code is needed.
How much does a fitness coaching app cost?
With Borel, from $20 a month for Pro plus Apple's $99 a year, and small cloud costs for logs and photos. Coaching platforms usually charge per client.
Can the app read Apple Health or Apple Watch data?
No. Borel apps don't read Apple Health or run on Apple Watch. They can count steps with the iPhone's own motion sensors, and clients can type in anything else.
Do I have to use Apple's in-app purchase for coaching?
For digital plans or content unlocked in the app, yes (Guideline 3.1.1). Live one-to-one coaching between two people may be paid another way under Guideline 3.1.3(d).
Can clients message their coach in the app?
Yes. Borel builds private conversations that only the client and coach can read. New messages show when the app is opened, since Borel apps don't send push notifications.
Can I show exercise demos?
Yes, with pictures and written cues: upload your own photos or describe an illustration for Borel AI to draw. Linking out to videos you already host works too.
Can the app remind clients to train?
Yes. Reminders are scheduled on the phone, like "Leg day at 18:00", using Apple's notifications. See reminders and notifications.
Will Apple approve a fitness app built with AI?
Apple reviews the app, not how it was made. A complete app with real features, a privacy policy, account deletion and no medical claims stands a good chance; Stamp checks the common reasons for rejection before you submit.
I started Borel because I wanted to make iPhone apps without a Mac or a team behind me. If this helped you build something, I would love to see it.
– Sigsten
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