React Native Paper
Material Design for React Native (Android & iOS)
Expensify uses agent-device. Mobile bug evidence and profiling are part of its documented usage story.
What you get
Buffering, controls, fullscreen, and resolution switching tuned per platform. Playback that just works.
Consistent remote navigation across screens and components, so viewers stay in control everywhere.
Quick launch, fluid transitions, and efficient state on older smart TVs and low-end boxes. Our Samsung TV rewrite cut TTI by 28.6%.
Apple TV top shelf, Android TV recommendations, voice search, enabled where each platform supports it.
One codebase for auth, browsing, and watch history, with UI adapted to fit each screen it runs on.
Automated pipelines, device testing, and store submission, so you ship reliably on every platform.
How we work together
Our senior engineers join your team to ship features, guide technical decisions, and strengthen delivery.
We take agreed work from technical planning to release, with clear responsibilities and progress you can see.
We address a performance, migration, or infrastructure challenge, or run training around your team’s needs.
Case studies




Streaming App Development
Ship a streaming app that meets platform standards across TV, mobile, and web, without growing your team.
We had been struggling with React Native application performance until we met Callstack.

We’ll connect you with the right expert within 24 hours.
Still have questions?
We build native apps for tvOS and Android TV, web for Tizen and webOS, plus mobile, all from one React Native codebase.
Yes. We share logic for auth, browsing, and watch history, with the UI adapted to fit each screen it runs on. There are no separate apps to maintain.
We map platform requirements early, enable features like Apple TV top shelf, Android TV recommendations, and voice search where supported, and meet each platform's store rules.
Yes. We tune startup, transitions, and state for older smart TVs and low-end boxes. Our Samsung TV rewrite cut time-to-interactive by 28.6%.
Yes. We join as an extension of your team to deliver feature parity across screens without growing your headcount.
We tune buffering, controls, fullscreen, and resolution switching per platform, so playback just works on every screen.
We build consistent focus across screens and components, so viewers never get trapped and stay in control on every remote.
We set up production-grade CI/CD with automated pipelines, device testing, and store submission, so you ship reliably on every platform.