Denis Zhurba

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BOXR — AI sports-coaching app

Founder, CEO & Product Lead (Kinetic Ventures) · 2022–2024 · acquired by a PE roll-up

Top-5 in the UK and top-10 in the US in Health & Fitness (Google Play, Top Free, Jul 2024); ~250k installs in the first 6 months; 4.6 rating; trial starts lifted ~5x to ~13%.

In 2022 I founded Kinetic Ventures to make high-quality coaching available on a phone, and built BOXR, an AI boxing-coaching app. Competitors had raised tens of millions and relied on bulky, expensive tracking; I built body tracking and gamification that run on a normal phone camera.

What I built. On-device computer vision (Google ML Kit / MediaPipe) with 97%+ tracking accuracy for real-time form feedback, RAG-LLM coaching suggestions, and fine-tuned TTS for in-app audio. I A/B-tested storefronts, onboarding, and paywalls — trial starts rose roughly 5x to about 13% (top decile). BOXR climbed the Health & Fitness charts to top-5 in the UK and top-10 in the US (Google Play, Top Free, July 2024), with ~250k installs in its first six months and a 4.6 store rating.

The pivot. I trialled in-gym hardware with 5+ UK gyms — custom Android devices with MDM — then made the call to go software-only after seeing the real cost and management overhead, shipping always-on AI workouts on smart screens instead. The company was later acquired by a private-equity roll-up.

BOXR / Kinetic AI workouts running on in-gym smart-screens.