G99 Labs

G99 Labs is a mobile, web, and backend development studio that helps startups and agencies take products from first commit to production. The team builds React Native apps for iOS and Android, Next.js web platforms, and FastAPI/Node.js backends, with expertise spanning architecture, development, testing, App Store and Google Play submission, and post-launch support.

G99 Labs specialises in consumer mobile apps, subscriptions and in-app purchases, dashboards, marketplaces, APIs, payments, real-time data, and release automation using tools such as Expo, EAS, TypeScript, PostgreSQL, and Sentry. It also supports “rescue” projects—resolving App Store review issues, unacknowledged purchases, billing defects, and broken release pipelines in existing codebases.

Based in Bijeljina, Bosnia and Herzegovina, G99 Labs works remotely with teams in the UK and EU. Its process includes a written scope with features, timeline, and pricing; early TestFlight and internal builds; end-to-end store submission; and ongoing support for updates, OS releases, and new features.