Available for collaboration

Crafting Mobile
Experiences

I'm Sergii Bilak — a software engineer building apps that people love on iOS and Android.

Apps I've Built

From fitness coaching to puzzle games — each app is crafted with care for great user experience.

BeFasta icon
BeFasta Running Training Plans
Health & Fitness
Innovative app for runners of all levels. Personalized training plans for 5K to marathon, powered by a patented algorithm and verified by certified running coaches.
Skull Treasures icon
Skull Treasures Match 3 Puzzle
Games • Puzzle
Over 1,000 exciting levels with vivid graphics and thrilling effects. Collect precious skulls, use powerful boosters and unique combinations to advance.
Time Machine icon
Time Machine: Read & Game
Games • Adventure
Interactive story and puzzle game. Guide protagonist Eugene through ancient worlds, make choices that shape the narrative, collect relics, and unlock multiple endings.
Computer Guy icon
Computer Guy
Games • Simulation
Hacker life simulator. Step into the world of hacking, build your setup, write code, and rise through the ranks in this addictive simulation game.
STRONG RUN icon
STRONG RUN Online Competitions
Health & Fitness
Organize and join running competitions in your city. Compete at distances from 200m to 10K, connect via Strava, track progress and win prizes.
BdzholoMarket icon
BdzholoMarket — Beekeeping Store
Shopping
Everything for beekeepers in one app. Browse hives, honey extractors, protective gear and equipment with easy navigation, quick checkout and current pricing.
Flappy Cities icon
Flappy Cities
Games • Arcade
Vibrant arcade game about reflexes, rhythm, and traveling the world. Fly through cities with unique atmospheres — from neon megacities to cozy European streets — dodge obstacles and set records.
Nektar24 icon
Nektar24 — Beekeeping Shop
Shopping
Everything for your apiary in one place. Browse hives, honey extractors, protective gear and supplies with easy navigation, quick checkout and fast delivery across Europe.

Software Engineer &
Mobile Developer

Versatile software engineer with expertise across the full development lifecycle. I build cross-platform mobile apps for iOS and Android, with a focus on integration, performance, and polished user experience.

My apps span health & fitness, gaming, e-commerce, and education — each one designed to solve real problems and delight users.

Node.js TypeScript Flutter Firebase
BeFasta Skull Treasures Time Machine Computer Guy STRONG RUN BdzholoMarket Flappy Cities Nektar24

How Can I Help?

If you have questions, issues, or feedback about any of my apps, I'm here to help.

General Questions

Have a question about how an app works, its features, or compatibility? Send me a message and I'll get back to you as soon as possible.

Bug Reports

Found a bug or something not working as expected? Please describe the issue, your device model, and OS version so I can investigate and fix it quickly.

Feature Requests

Have an idea for a new feature or improvement? I love hearing from users — your feedback directly shapes future updates.

Account & Privacy

Questions about your data, privacy, or account? I take your privacy seriously. Reach out and I'll address your concerns promptly.

Reach out directly at serge@bilak.dev — I typically respond within 24–48 hours.

Let's Work
Together

Have a project idea, partnership proposal, or just want to say hi? Drop me a message.