# Cross-platform app

> A cross-platform app is a mobile app written once and run on both iOS and Android. Flutter and React Native are the best-known tools. Instead of two separate apps there is one codebase, which cuts build time and maintenance.

- URL: https://radkod.com/en/glossary/cross-platform
- Publisher: RadKod
- Published: 2026-07-30

## What is a cross-platform app?

A cross-platform app is one app that runs on more than one operating system. With the native approach, you write two apps: one in Swift for iOS and one in Kotlin for Android. With the cross-platform approach, you write it once in a tool such as Flutter or React Native and ship both store versions from that code.

Here is an everyday case. A chain of beauty salons wants a booking app. Going native means two teams, two codebases and two test cycles. Moving a button means changing it twice. Going cross-platform means one codebase, so a change is made once and reaches both apps. Users rarely notice any difference. Flutter draws screens with its own rendering engine and runs smoothly on both platforms.

## Why does it matter?

One codebase means shorter development and less upkeep. The team stays small, and new releases reach both platforms at once. It is not right for everything. Apps that lean heavily on the camera, Bluetooth or features specific to one operating system may need native code, and a cross-platform app can include native parts where needed. We compare the two in [native or Flutter](/en/blog/native-or-flutter). See how we build apps on our [mobile app development](/en/services/mobile-app-development) page.

## Frequently asked questions

### Is a cross-platform app as fast as a native one?

For most business apps, such as bookings, orders, catalogues and memberships, users see no difference. Heavy graphics or deep hardware use can favour native.

### Is a cross-platform app cheaper?

It usually needs less work than two native apps, but not half. Design, the back end and store preparation are needed either way.

### Can a Flutter app go on the app stores?

Yes. Flutter apps are published on the App Store and Google Play like any other app and go through the same review.

## Sources

- [Flutter](https://flutter.dev), Google