QSD

Based in Mostar, QSD has built mobile applications for startups and global businesses since 2010. The company works across the full software lifecycle, taking products from prototyping and UX design through development, QA, and post-launch maintenance rather than handing off after a single build phase.

Development covers native iOS and Android work in Java, Kotlin, and Swift, alongside hybrid builds using React Native and KMM. Backend and API work draws on Node.js, Python, Ruby, Nest, and Flask, with PHP projects handled in Laravel, CodeIgniter, CakePHP, and Symfony. Frontend teams build in React.js, Vue.js, and Angular, and mobile UX and graphic design are handled in-house alongside QA and app testing before release.

Client work spans several recognizable products: Jaumo, a dating platform; The Wonder Weeks, an app holding the No. 1 position on both the App Store and Play Store with millions of active users; and PubNub, described as the world's largest realtime communication platform and realtime infrastructure-as-a-service provider. These projects reflect QSD's focus on shipping apps that scale to large, active user bases rather than one-off builds.