What is Flutter?
Flutter is an open source framework developed and supported by Google. Frontend and full-stack developers use Flutter to build an application’s user interface (UI) for multiple platforms with a single codebase.
When Flutter launched in 2018, it mainly supported mobile app development. Flutter now supports application development on six platforms: iOS, Android, the web, Windows, MacOS, and Linux.
How does Flutter help app development?
Flutter simplifies the process of creating consistent, appealing UIs for an application across the six platforms it supports.
Because Flutter is a cross-platform development framework, we’ll first compare it to native development. Then, we can highlight features that are unique to Flutter.
Native app development compared to cross-platform app development
Coding an application for one specific platform, such as iOS, is called native app development. By contrast, cross-platform app development is building an application for multiple platforms with a single codebase.
Native app development
Because developers code for a specific platform in native app development, they have full access to native device functionality. This generally leads to higher performance and speed compared to cross-platform app development.
On the other hand, if you want to launch an application on multiple platforms, native app development requires more code and more developers. In addition to these expenses, native app development can make it harder to launch on different platforms at the same time with a consistent user experience. This is where cross-platform app development frameworks like Flutter can be useful.
Cross-platform app development
Cross-platform app development allows developers to use one programming language and one codebase to build an application for multiple platforms. If you’re releasing an application for multiple platforms, cross-platform app development is less costly and time-consuming than native app development.
This process also lets developers create a more consistent experience for users across platforms.
This approach can have drawbacks compared to native app development, including limited access to native device functionality. However, Flutter has features that make cross-platform app development smoother and highly performant.
The advantages of Flutter
Here are some ways that Flutter stands out as a cross-platform development framework:
- Close-to-native performance. Flutter uses the programming language Dart and compiles into machine code. Host devices understand this code, which ensures a fast and effective performance.
- Fast, consistent, and customizable rendering. Instead of relying on platform-specific rendering tools, Flutter uses Google’s open-source Skia graphic library to render UI. This provides users with consistent visuals no matter what platform they use to access an application.
- Developer-friendly tools. Google built Flutter with an emphasis on ease-of-use. With tools like hot reload, developers can preview what code changes will look like without losing state. Other tools like the widget inspector make it easy to visualize and solve issues with UI layouts.
What programming language does Flutter use?
Flutter uses the open-source programming language Dart, which was also developed by Google. Dart is optimized for building UIs, and many of Dart’s strengths are used in Flutter.
For example, one feature of Dart used in Flutter is sound null safety. Dart’s sound null safety makes it easier to detect common bugs called null errors. This feature reduces the time developers spend on code maintenance and gives them more time to focus on building their applications.
What are widgets in Flutter?
In Flutter, developers build UI layouts by using widgets. This means everything a user sees on a screen, from windows and panels to buttons and text, are made of widgets.
Flutter widgets are designed so developers can easily customize them. Flutter achieves this through a composition approach. This means most widgets are made up of smaller widgets, and the most basic widgets have specific purposes. This allows developers to combine or edit widgets to create new ones.
Flutter renders widgets using its own graphic engine instead of relying on a platform’s built-in widgets. This way, users will experience a similar look and feel in a Flutter application across platforms. This approach also provides flexibility to developers, because some Flutter widgets can carry out functions that platform-specific widgets can’t.
Flutter also makes it easy to use community-developed widgets. Flutter’s architecture supports having multiple widget libraries, and Flutter encourages the community to build and maintain new ones.
Types of Flutter widgets
Flutter comes with an extensive widget catalog from the time you download it. The catalog has 14 categories, which include styling, Cupertino (iOS-style widgets), and Material Components (widgets that follow Google's Material Design guidelines).
Flutter also comes with layouts and themes included, helping developers to build right away.
How is Flutter supported?
Flutter is supported by Google and an active open source community on Reddit, Discord, Slack, Stack Overflow, and Gitter. Google has consistently updated Flutter since its release in 2018, including with a Flutter 3 update in 2022 which extended stable support to macOS and Linux.
To make Flutter easier to learn, Google has written extensive documentation and tutorials on Flutter’s site. To engage with Flutter users, Google also hosts global events, promotes community projects, and sponsors developer challenges. Upcoming events can be found on Flutter's site.
Flutter’s community has created thousands of third-party packages and excellent tools that streamline the developer experience. These libraries are available at pub.dev.
How does AWS support Flutter?
Flutter helps you build the parts of an application that users see. But application development requires many features that users don’t see, like authentication, file storage, and analytics. This is where AWS Amplify and Amplify Flutter come in.
AWS Amplify is a framework for building secure, scalable mobile and web applications. With support for iOS, Android, web, React Native, and Flutter, AWS Amplify makes it quick and easy for you to build applications powered by AWS.
Amplify Flutter is a set of tools and libraries that allows you to provision, build, and deploy backends for Flutter applications. You can use Amplify Flutter to connect your Flutter applications to AWS and solve common backend needs.
Use Amplify Flutter as your backend solution
Amplify Flutter allows you to work with AWS to add common backend features to your Flutter application:
- Analytics. Amplify Flutter allows you to collect tracking data for users in Amazon Pinpoint. You can easily record events and customize metrics and attributes for your needs.
- APIs. Amplify Flutter has robust API capabilities. The GraphQL API helps you retrieve data in your backend, and it's backed by AWS AppSync. REST APIs and handlers use Amazon API Gateway and AWS Lambda to help you make requests to your backend.
- Authentication. Amplify Flutter allows you to authenticate users and implement sign-up and sign-in forms as well as multi-factor authentication. Behind the scenes, it provides the necessary authorization to the other Amplify categories. Amplify Flutter supports Cognito User Pool and Identity Pool from the time you start using it.
- DataStore. Amplify Flutter lets you use distributed, shared data without writing extra code for offline and online scenarios. This makes working with distributed, cross-user data just as simple as working with local-only data. Amplify DataStore versions data automatically and uses AppSync to implement conflict detection and resolution in the cloud.
- Storage. Amplify Flutter lets you upload, download, and delete objects in storage. And Amplify Flutter comes with built-in support for Amazon Simple Storage Service (Amazon S3).
Learn more about Amplify Flutter.
