What is Flutter?

Flutter is an open-source UI framework created by Google for building natively compiled applications across mobile, web, and desktop platforms from a single codebase. First released as a stable product in December 2018, Flutter has grown into the most popular cross-platform development framework, used by over 42% of cross-platform developers worldwide according to Statista's 2024 Developer Survey.

How Flutter Works

Flutter uses Dart, a modern programming language also developed by Google. Unlike other cross-platform frameworks that rely on native UI components or web views, Flutter takes a fundamentally different approach. It ships its own rendering engine -- originally Skia, now transitioning to Impeller -- that draws every pixel on screen directly.

The framework is built around a widget tree architecture. Everything in Flutter is a widget: buttons, text fields, layouts, animations, and even the app itself. Developers compose these widgets together to build complex interfaces. When state changes, Flutter's efficient diffing algorithm redraws only the widgets that need updating, delivering smooth 60fps (and 120fps on supported devices) performance.

Key Benefits

Single codebase. Write your application once and deploy it to iOS, Android, web, Windows, macOS, and Linux. This eliminates the need for separate development teams for each platform.

Hot reload. Flutter's stateful hot reload lets developers see code changes reflected in the running app in under a second without losing application state. This dramatically accelerates the development and debugging cycle.

Custom UI without compromise. Because Flutter controls every pixel, designers are not limited by platform-specific UI components. You can create fully custom interfaces that look identical on iOS and Android, or tailor the experience per platform.

Near-native performance. Flutter compiles to native ARM machine code, not interpreted JavaScript. Applications built with Flutter achieve performance that is comparable to native apps for the vast majority of use cases.

What Flutter Is Used For

Flutter is used to build a wide range of applications, including consumer mobile apps, internal business tools, e-commerce platforms, fintech applications, and progressive web apps. Its versatility makes it suitable for everything from simple MVPs to complex enterprise solutions.

Who Uses Flutter

Major companies have adopted Flutter for production applications. Google uses it for Google Pay and Google Classroom. BMW built its connected car experience in Flutter. eBay Motors, Alibaba's Xianyu marketplace, and Nubank (Latin America's largest digital bank) are all Flutter-powered applications serving millions of users.

Flutter vs React Native

The two leading cross-platform frameworks are frequently compared. Flutter offers superior UI consistency across platforms and faster rendering through its custom engine. React Native leverages the massive JavaScript ecosystem and may be a better fit for teams with existing React and JavaScript expertise. Both are excellent choices, and the right decision depends on your team's skills and project requirements.

When to Choose Flutter

Flutter is the strongest choice when you need a custom-designed UI that stands out, want to target multiple platforms (especially mobile plus web), are starting a new project without legacy JavaScript code, or need high-performance animations and transitions.

Build with Flutter at App369

At App369, Flutter is our primary framework for cross-platform development. We have delivered dozens of Flutter applications ranging from startup MVPs to enterprise-grade solutions. Get in touch to discuss how Flutter can accelerate your next project.