How to Build a Fitness App? Here’s What You Need to Know

The global fitness app market is projected to reach over $30 billion by 2026, and it’s not slowing down. From tracking daily steps to delivering personalised workout plans, fitness apps have become an essential part of how people manage their health.

If you’re thinking about building one, the opportunity is huge but so is the competition. Success comes down to making the right product development choices from the start: features, user experience, data security, and engagement strategies.

In this post, we’ll break down the key steps, decisions, and considerations to build a fitness app. Let’s get started.

What is a fitness app?

A fitness app is a software application designed to help users improve their physical health, develop healthier habits, or track their fitness goals. These apps can offer various features, including step counters, calorie tracking, workout libraries, real-time coaching, and integration with wearables like Fitbit, Apple Watch, and Garmin.

Unlike traditional fitness centres and gyms, a fitness app offers the ease of doing exercises and maintaining their health anywhere they are, be it their homes or their office.

Popular types of fitness apps

There is a plethora of fitness and health-related apps available on the app stores today. We have categorised them into four main types, based on their purpose, features and target audience. We have discussed each type in detail below.

Workout and Exercise Apps

These types of fitness apps are used to help people with their exercise and workout regimes. Most workout and exercise apps serve the function of a personal trainer by building an exercise plan according to your fitness goals and keeping track of them for you. Users can set their fitness goals (such as losing weight, gaining muscle or toning their abs) and select the area of the body they want to work on (for instance, Full Body, Lower Back, Upper Body, or Core Strength) and get a customised exercise plan based on it.

Example: Nike Training Club, SWEAT, Fitbit Coach, Jefit

Diet and Nutrition Apps

A controlled diet is a major aspect of fitness and there are numerous apps that help people manage their daily dietary and nutritional intake based on their fitness goals. Users can log in their meals throughout the day and know the total number of calories consumed. They can search the food database to find the nutritional value of different foods or scan the barcode of packaged food items – this comes especially handy while shopping.

Like other fitness apps, users can set their fitness goals and level of physical activity and know the recommended calorie consumption limit based on their fitness goals.

Example: MyFitnessPal, Waterlogged, Lose It!, MyPlate Calories Tracker

Activity Tracking Apps

Activity tracking apps keep a track of your physical activity throughout the day using motion sensors in your smartphone or wearables. They track different activities such as the number of steps walked, flights climbed, distance travelled and calories burned in a day. Some activity tracking apps are specifically designed for activities like running, cycling, or swimming.

The two most important aspects of building an activity tracking fitness app are (i) integration with GPS and (ii) compatibility with different fitness wearables.

Example: Nike Run Club, Runtastic Running, Fitness Tracker

Bespoke Apps For Personal Trainers or Studios

Bespoke apps have become relevant in the times after Covid-19 when gyms and training studios have been shut down due to the pandemic. This has impacted trainers, gym-goers and studio owners equally. In such a situation, custom-built apps offered a viable solution for trainers and fitness enthusiasts to connect virtually and continue their exercise and training from their homes.

The functionality and feature of such apps can vary greatly depending on the specific requirements of the personal trainer or studio. It can be for the purpose of scheduling training sessions or it can have a video streaming feature so the trainer and users can do live workout sessions from within the app.

Key steps to create a fitness app

Building a fitness app is not just about coding. It requires business strategy, market understanding, technical execution, and user engagement planning.

Here is a step-by-step breakdown on how to build a fitness app:

Step 1: Research the market and choose a platform

Before you start building, do deep research of what, why and how your app will be and define a roadmap and set goals. Ask yourself questions like:

• Who is your target audience? Are you targeting yoga lovers, strength trainers, or busy professionals?

• What is your competition doing? Analyse apps like MyFitnessPal, Strava, and Nike Training Club. What works? What’s missing?

• What is your audience looking for? Build user personas. What are their pain points and motivations?

Then, choose one or more platforms where your app will be available. It will be based on your target audience, their demographics and your budget. Here are four core platforms:

• iOS: Popular in North America and Western Europe

• Android: Dominates in Asia, Africa, and emerging markets

• Cross-platform: Ideal for MVPs targeting global audiences

• Web app (PWA): Great for supplementary access or admin panels

Step 2: Identify the prototype

The prototype is a functional or visual representation of your app’s key features. It helps stakeholders visualise the product, and guides the development team as to how the app should look and work like.

Making a prototype involves four main things:

1. Creating wireframes: This is simply a rough sketch of how you would like your app to be. It can be done on a paper or on digital apps like Figma or Sketch.

2. Define MVP features: Start with the features that you think are necessary to include in your app. Focus on those before adding in any extra features. Here are some basic MVP features that you can include in your fitness app:

• Account creation/login
• Goal setting (e.g. weight loss, step count)
• Workout/video library
• Real-time performance tracking
• Push notifications for reminders
• Basic analytics/dashboard

3. Develop user journeys: Map out how the users will interact with your app. This involves features like scrolling and making icons that will redirect them to another page or activity.

4. Build an interactive prototype: While wireframes are referred to as low-fi prototypes, tools like Figma or InVision can also be used to make high-fi prototypes to simulate user experience.

Step 3: Choose the right tech stack

Choosing the right technology stack is essential for scalability, performance, and integration. We have briefly listed four tech stacks that you can use and their pros and cons.

Native Apps

These are apps built specifically for a single platform that use platform-specific programming languages. They are known for smooth performance and full access to device features.

·        Languages: Swift (iOS), Kotlin (Android)

·        Pros: High performance, better hardware access, excellent UX

·        Cons: Requires separate codebases for iOS and Android

Cross-Platform Apps

These apps use a single codebase to run on both Android and iOS. They are ideal for teams looking to reduce development time and costs while still reaching a wide user base.

• Tools: React Native, Flutter

• Pros: Shared codebase, faster to develop

• Cons: May have performance limits in sensor-heavy apps

Progressive Web Apps (PWAs)

PWAs are web applications that work like mobile apps but run in a browser. They don’t require app store approval and can be accessed instantly.

• Tools: HTML, CSS, JavaScript

• Pros: No app store approval, accessible via browser

• Cons: Limited offline functionality and hardware integration

No-Code Platforms

These platforms let you build fully functional apps without writing code. They are perfect for MVPs, startups, or non-technical founders looking to launch quickly.

• Platforms: Adalo, Glide, Bubble

• Pros: Fast prototyping, low cost

• Cons: Limited customisation and scalability

Your fitness app will serve multiple users and may require a multi-tenant architecture. Check out our guide: Everything you need to know about multi-tenant architecture for more information.

Step 4: Build and test the app

At this stage, developers can now take the idea and inspiration from the prototype to make a functioning product. This involves three key things:

1. Design and development process:

• Creating UI/UX designs based on the prototype

• Building front-end and back-end architecture

• Implementing APIs and third-party integrations (payment gateways, wearable data, etc.)

2. Testing:

• Unit testing: Checking individual components and features

• Functional testing: Ensuring that the is app performing as intended

• Usability testing: Testing with real users to see what works during the development stage

• Beta testing: A soft launch with a small number of users to gather feedback

3. Project timeline:

On average, making an MVP can take from 6 to 12 weeks. On the other hand, creating an app with all the features may take 4 – 6 months. However, it also depends on the complexity of the project, like what type of fitness app you are making and what features do you want to include in it.

Read also: How to build a travel app

Step 5: Release and maintain

Once your app has been created and tested, it is time to go launch. You can submit it to the Apple App Store and/or Google Play depending on the platform(s) you have chosen. At this point, you will also need to promote the launch of your app via various channels like email, social media and influencer marketing to reach your intended audience.

However, it does not just end at deploying the app. Having a good marketing and promotion campaign may get people to download your app, but you need much more to make them stay. To make it successful, you need to regularly maintain and update the features in your app, like adding new trends or changing old ones that your users no longer use as much.

If you’re interested in building a different type of SaaS product, check out our article: How to build a SaaS product

How much does it cost to build a fitness app?

An app building project pricing can vary greatly depending on a number of factors, like:

• The idea of the app itself (making a fitness app would cost different from making a social media app)

• Custom UI/UX designs

• What kind of prototype and features you want in your app

• Subscription/payment systems

• Deployment platform (iOS, Android, or both)

• The size of the intended user base

• Number of screens (app pages)

• Backend infrastructure (e.g. cloud hosting, analytics)

As per GoodCore’s pricing policy, the cost of a bespoke software development project, based on its size and complexity, could fall in the range of:

·        Small project: £10,000 – £35,000

·        Medium-sized project: £40,000 – £65,000

·        Large project: £70,000 +

Fitness app development best practices

Here are some proven practices by our industry experts to ensure your fitness app’s long-term success:

• Start with a basic MVP. Don’t overload the first version; test and iterate.

• Go for a user-first design, with simple navigation, easy to understand user interface (UI), and visual cues for a smooth user experience (UX).

• Offer different fitness levels to cater to different audience segments instead of having a one-for-all approach.

• Gamification has become a trend which you can also use in your fitness app, like having badges, streaks, and points to drive user motivation.

• You can offer personalised recommendations for workouts or diet plans based on user history and goals.

GoodCore’s experience in fitness app development: Weight Loss Resources

One of our standout projects in the fitness tech space was with Weight Loss Resources, a UK-based web platform offering calorie tracking, food budgeting, and community challenges for individuals pursuing healthier lifestyles. The platform had been around for over two decades and was heavily reliant on a legacy Core PHP codebase maintained by a single developer.

We took over full responsibility for maintaining and evolving the platform. Our team started by performing a deep dive into the existing code and system structure, ensuring a smooth handover. From there, we modernised the tech stack, redesigned the UI/UX for better engagement, and rolled out brand-new features like weight loss challenges and improved admin dashboards with advanced analytics and search functionality.

These updates helped stabilise the platform, as well as boosted user signups by 25% and significantly improved overall user satisfaction. By resolving device integration issues and streamlining reporting workflows, we helped Weight Loss Resources move from survival mode to scalable growth.

Read full case study →

Final Thoughts

Building a successful fitness app takes more than just an idea. It demands strategy, technical expertise, and a clear understanding of user needs. With the right development partner, you can create a product that improves lives, scales fast, and becomes a profitable venture.

FAQs

What would be the minimum cost to build an MVP of a fitness app with your development company?

For a basic MVP that includes core features like user registration, workout libraries, goal tracking, and push notifications, the development cost typically starts from £10,000 to £20,000. This range may vary based on design complexity, feature set, and whether the app is built for one platform or both iOS and Android. Additional features like wearable integration or meal tracking will increase the cost. A proper scoping session can help determine a more accurate estimate.

How profitable are fitness apps?

A well-niched app with a loyal community can scale rapidly. Top players like SWEAT, MyFitnessPal, and Strava generate millions in revenue annually. Profitability depends heavily on your ability to retain users, provide real value, and use effective monetisation strategies like subscriptions, in-app purchases, or premium content.

Can you build a fitness app in two weeks?

A basic no-code MVP or interactive prototype, can be built within two weeks. However, if you’re looking for a custom-built app with backend development, user authentication, and API integration, it typically takes 6 to 8 weeks minimum. It depends on the complexity of your features and the development approach you choose (e.g. native vs no-code).

What are the top 5 most successful fitness apps?

Some of the most popular and revenue-generating fitness apps globally include:

1. MyFitnessPal: Leading in nutrition tracking

2. Nike Training Club: Offers guided workouts for all levels

3. Fitbit: Syncs with wearable devices for health insights

4. Strava: Popular with runners and cyclists for tracking and community

5. SWEAT: Tailored workouts and plans, especially popular among women
   These apps succeed because they offer real value, strong branding, and consistent updates.

What are the monetisation strategies for fitness apps?

There are several proven ways to monetise a fitness app:

• Freemium Model: Offer basic features for free and lock advanced content behind a paywall

• In-App Purchases: Sell workout plans, personalised diets, or branded merchandise

• Ads: Generate revenue by showing targeted ads (e.g. sportswear, supplements)

• Subscriptions: Charge users monthly or annually for access to premium features and content

• Affiliate Programs: Earn commission by promoting third-party fitness gear or nutrition products.