From Idea to MVP in 10 Days: A Case Study

FitPulse started as an idea on a napkin: a fitness app that personalizes training plans and tracks progress. The founding duo — a personal trainer and a marketing manager — had a budget of €2,800 and one wish: go live in 2 weeks. Here's their story.

Days 1-2: Scope and setup. The assigned Viber analyzed the requirements and created a detailed concept in 4 hours: React Native app with Supabase backend, AI-powered training plan generation via OpenAI API, and Stripe for the subscription model. Tech stack decision: deliberately lean, deliberately scalable.

Days 3-5: Core features. Authentication, user profiles, and the training plan engine were up and running. The Viber used AI-powered scaffolding to accomplish in hours what used to take days. The training plan AI was trained on 500 pre-built templates and generated personalized plans based on fitness level, goals, and available equipment.

Days 6-7: UI/UX polish. The design followed a minimalist dark theme with accent colors for motivation elements. Animated progress bars, a calendar widget, and push notifications were integrated. The founders' feedback after the weekend review: 'This looks like an app that cost 10x more.'

Days 8-9: Testing and refinement. Automated E2E tests on both platforms, performance optimization, and accessibility review. The Viber fixed 23 bugs found by automated testing and optimized the app's load time from 2.8s to 0.9s.

Day 10: Launch. The app went live on both app stores. First day: 47 downloads. After one week: 312 active users. The conversion rate from free trial to subscription was 18% — significantly above the industry average of 8-12%.

The FitPulse project shows what's possible when AI-native development meets clear scope. No endless back-and-forth, no scope-creep surprises — just an experienced Viber who uses the right tools to maximize the budget. Today, FitPulse has over 5,000 active users and is preparing a Series A round.