A coaching app that keeps clients accountable between sessions.

Health & Fitness · Medium App

The client.

A personal trainer based in South Australia with over ten years of experience coaching clients in person. He was consistently booked out weeks in advance, but every client still relied on him being physically there. There was no way to grow without burning out.

He wasn't trying to become a tech company. He wanted something that kept his clients on track between sessions without him having to send texts, chase check-ins, and email PDF programs every Monday morning.

The idea.

A mobile app where personal trainers deliver structured programs to their clients. The trainer builds the plan, the client follows it on their phone, logs their sessions, and checks in with progress photos and notes. The trainer sees everything in a dashboard without having to ask.

This wasn't another fitness app full of stock workouts. The trainer is the product. The app just handles the stuff that currently gets done over text and email.

The challenge.

Two user types with very different needs. The trainer needs to build programs quickly, manage multiple clients, and see who's doing the work. The client needs something dead simple. Open the app, see today's workout, do it, log it.

The gym environment added constraints. Clients use the app mid-workout with sweaty hands, often in poor lighting, and sometimes with no reception. The interface needed to work offline, with large touch targets, and never require more than one tap to get to the next exercise.

Scope was the other challenge. The client had ideas about nutrition tracking, in-app messaging, wearable integrations, and a community feed. We had to keep version one focused on the core loop: trainer programs, client logs, progress visibility. Everything else was documented for later.

The process.

Week 1. Discovery and research

We started by looking at how the client actually runs his coaching right now. Spreadsheets, WhatsApp groups, voice notes, PDF programs emailed out every Monday. It worked, but only because he was doing all the chasing himself. We mapped out the whole process from first consultation through to program delivery and progress tracking, and found every spot where things fell apart.

I looked at twelve existing fitness apps. Most were built for people training themselves, not for trainers managing real clients. The ones that did target trainers were bloated and hard to use on the client side.

Week 2. Flows and wireframes

We mapped out both sides of the app in parallel. On the trainer side: client management, program builder, progress dashboard, and notification controls. On the client side: daily workout view, exercise detail with video reference, session logging, and progress check-in.

The program builder was the most complex piece. The trainer needed to create multi-week programs with exercises grouped by day, each with sets, reps, tempo, and rest. We designed a drag-and-drop interface that made building a four-week program feel fast rather than tedious.

Weeks 3 and 4. Design

Dark background, high-contrast text, nothing decorative. This is something you use between sets with chalk on your hands, not something you browse on the couch. The workout screen was designed to be readable at arm's length on a phone propped against a weight rack.

We spent extra time on the progress dashboard for trainers. A single screen that shows which clients completed their sessions this week, who's falling behind, and whose check-in is overdue. The trainer told me if he could see that one screen every morning, it would change how he runs his business.

Week 5. Prototype and handoff

The prototype covered the full trainer and client experience. The client tested it by putting it in front of two of his real clients during a session. Both understood it straight away. No explanation needed.

I delivered annotated Figma files, a component inventory, and a clear MVP scope document. The client had already started conversations with a developer before the design was even finished.

The result.

A complete Figma design covering both the trainer dashboard and client mobile experience. A clickable prototype tested with real users in a real gym. Annotated developer handoff documentation. A scoped MVP with future features clearly documented for later versions.

The client came in sending PDF programs over email and chasing check-ins by text. He walked out with something that could replace all of that and let him coach clients he never has to see in person.

What made this project work.

• The client had ten years of coaching experience. Every feature request was grounded in a real situation he'd dealt with hundreds of times.
• We designed for the gym environment first. If it worked mid-workout with sweaty hands and no reception, it would work everywhere.
• Keeping version one focused on programs, logging, and progress meant the app did one thing well instead of ten things badly.
• Putting the prototype in front of real clients during a real session told us more than any usability test ever could.

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