KEEP.FIT
A bespoke digital platform combining a modern website and fully featured mobile application.
Project Overview
KEEP.FIT is an online fitness platform designed for anyone looking to train, improve, and reach their goals. Available across both web and mobile, the entire system is custom-built from the ground up - combining training, content delivery, and user management into one seamless experience.
This project brings together many of our core services in one end-to-end solution - from design and branding to backend engineering, API development, and mobile app delivery. Let’s take a closer look at how it was built.
Project Goals
Client Objective
To build a scalable fitness platform accessible to anyone, working seamlessly across web and mobile, and enabling users to follow programmes, track progress, and access premium content.
Our Deliverables
A cohesive digital experience including web platform, native mobile apps, user authentication, content management, automated notifications, and a robust backend API.
Platform Features
Below are some of the core features that power the KEEP.FIT experience — along with a look at how each one is engineered behind the scenes.
Personalised Dashboards
Track your progress, achievements, and goals at a glance.
Technical: Real-time data aggregation, cached metrics, and optimised queries ensure fast dashboard loading.
Daily Streaks
Stay motivated with daily streaks that reward consistency.
Technical: Background jobs verify streak activity using scheduled routines and secure validation logic.
Session Manager
Follow workouts in real time with clear guidance and timers.
Technical: Efficient API calls, lightweight state syncing, and client-side timers for smooth live sessions.
Community Forums
Join discussions, share tips, and stay inspired with the community.
Technical: Fully bespoke forum module with thread management, moderation tools, and role-based permissions.
Exercise Library
Access 900+ guided exercises with clear instructions and videos.
Technical: Powered by a custom CMS with video hosting, metadata tagging, and optimised media delivery.
Gym Links
Connect your KEEP.FIT profile to the gyms you visit.
Technical: Integrated with Google Maps for location services, enabling gym mapping, proximity lookups, and seamless profile–gym connections.
Technical Architecture
Behind KEEP.FIT is a robust technical foundation that enables smooth cross-platform experiences, secure data management, and reliable access to fitness content.
Frontend Technology
KEEP.FIT required fast, modern interfaces across web and mobile, using a component-driven approach for consistency and scalability.
- Web: ASP.NET Core + Razor/Blazor components
- Mobile: .NET MAUI (iOS & Android)
- UI: Component-based structure
- Performance: Efficient rendering with minimal redraws
API & Backend
A secure and scalable backend powering real-time features, authentication, and external integrations.
- Language: C#
- API: ASP.NET Core REST API
- Jobs: Background tasks & schedulers
- Admin: Full CMS with Admin Controls
Database & Data Layer
A secure, high-performance relational architecture designed for long-term growth and reliability.
- Database: SQL Server
- ORM: Entity Framework Core
- Schema: Normalised relational model
- Security: Encryption + ACL
- Scaling: Indexing + caching strategy
Identity & Single Sign-On
KEEP.FIT includes a modern identity layer to provide secure authentication, user management, and single sign-on across all platforms.
- Identity Provider: Duende IdentityServer (formerly IdentityServer4)
- Protocols: OAuth2 / OpenID Connect
- SSO: Unified login for web + mobile
- User Roles: Built-in role & claim-based access
- Security: Hardened token flows & refresh token rotation
Branding & Visual Identity
KEEP.FIT needed a bold, modern identity that resonated with fitness, performance, and digital accessibility. We developed a clean visual system including:
Brand Colours
Logo Variants
Web Logo
App Icon
Typography
Mulish – Heading
This is body text using the Mulish typeface. It is modern, clean, and highly readable, making it suitable for both UI and long-form content.
Small text example — using Mulish at a lighter weight.
Platform Infrastructure & Integrations
KEEP.FIT is powered by a secure, scalable cloud foundation with integrated payment services, analytics, and automated workflows.
- AWS cloud hosting with high availability, auto-scaling and secure managed services
- Cloudflare protection including DDoS mitigation, WAF rules and global CDN caching
- Stripe integration for secure payments, subscriptions and webhook-driven automation
- Analytics stack including Google Analytics, Hotjar and Meta Pixel for behavioural insights
Key Engineering Highlights
KEEP.FIT is built on a carefully engineered foundation that combines AI, data architecture, and scalable infrastructure. The highlights below showcase the core technical components that enable the platform to run smoothly across both web and mobile.
AI-Enhanced Content Generation
We developed a custom AI Agent trained on KEEP.FIT’s full exercise library, including movement descriptions, equipment types, muscle groups and workout structures. This allows the team to generate personalised challenges, workouts and training sessions simply by prompting the agent - with every output based entirely on verified first-party content.
The Agent understands exercise relationships, difficulty levels and programme flow, enabling it to assemble structured training plans that match KEEP.FIT’s tone, coaching style and technical standards.
Scalable Data Architecture
KEEP.FIT is powered by a carefully structured database containing over fifteen relational schemas - covering exercises, workouts, programmes, user metrics, session history, gyms, challenges, achievements, content, and many more.
Each schema is designed for clarity, performance and future growth. Normalised relationships, indexing strategies and caching layers ensure the platform can scale while returning results instantly across the web and mobile apps.
Challenges & Solutions
To achieve this, we built a clear separation of concerns: a standalone backend architecture (ASP.NET Core) and independent front-end platforms (web + .NET MAUI mobile).
Both the website and mobile app communicate with the same API, sharing user data, authentication, and business logic — while remaining fully decoupled.
This means:
• The system stays consistent across all devices
• Future frontend technologies can be swapped in without rebuilding the backend
• Maintenance is simpler, faster, and less error-prone
The result is a seamless cross-platform experience backed by a flexible, future-proof architecture.
To achieve this, we designed the system with performance-first principles:
• Optimised API endpoints for quick data retrieval
• Background jobs to handle streaks and progress calculations without slowing the user interface
• Caching layers to reduce unnecessary database calls
Together, these ensure the app stays smooth, responsive, and consistent — even as user activity grows.
We built a custom CMS tailored specifically for the platform, giving the KEEP.FIT team full control over:
• Exercise content (videos, instructions, variations)
• Workout plans and structured training programmes
• User-created challenges and custom sessions
• Blog articles and educational content
• Forum moderation and community tools
• Gym listings and location-based features
Under the hood, this is powered by scalable, well-structured database models and modular backend components - ensuring the CMS can grow with the platform as new features and content types are added.
We integrated Stripe with webhook-driven automation so renewals, failed payments, cancellations, and plan changes happen automatically, keeping user access fully in sync.
We implemented a secure Single Sign-On (SSO) setup using OAuth2 and OpenID Connect, powered by Duende IdentityServer. This provides:
• One secure login across all platforms
• Role- and claim-based access controls
• Strong token security with refresh token rotation
• A central identity service that protects user data
This approach ensures a consistent, secure authentication experience everywhere the user logs in — web, iOS, or Android.
Project Results
KEEP.FIT launched as a polished, high-performance digital product - delivering a smooth training experience across web and mobile, supported by a scalable and secure backend. The outcomes below represent the measurable impact of the work delivered.
Faster User Experience
Rapid navigation and real-time content delivery provide a smooth, responsive experience across all platforms.
Increased User Engagement
Features like daily streaks, personalised dashboards and guided sessions help boost motivation and long-term retention.
Stable & Scalable Foundation
A robust architecture built to support growth, high uptime and continuous feature expansion - without slowing down.
Explore the platform yourself - visit the live KEEP.FIT web application at keep.fit.
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