What is Flutter?

Flutter is a great choice for cross-platform mobile app development when you need your app to be fast, beautiful, and perform well. Additionally, if you need to reach a global audience, Flutter is the best option as it supports internationalization.
Azumo Research
March 22, 2024
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‍Flutter is a Powerful and Reliable SDK for Cross-Platform Mobile App Development

Flutter is a cross-platform software development kit (SDK) for mobile app development that was created by Google. Flutter uses Dart programming language and it is used to create apps for Android and iOS devices. Because it is cross-platform, a single code base can be used to create apps with a native look and feel on both Android and iOS devices.

Flutter is powerful and reliable, offering vast creative possibilities to build beautiful applications quickly. Thanks to its features and architectural decisions, the development process on Flutter is fast, making it suitable for building quick prototypes and MVPs as well as complex apps and games.

If you're looking to create amazing cross-platform mobile apps, Flutter is definitely worth checking out!

The Advantages to Using Flutter

One major drawback of building a native iOS or Android app is the time and effort required to create two separate codebases. Building a cross-platform app with a framework like Flutter can help to reduce development time and costs, while also making it easier to reach users around the world. Additionally, creating apps that have a native look and feel helps to improve the user experience and increases adoption.

As a mobile developer we get asked often whether to use a cross platform solution or build native app. While we always have a thoughtful response we almost always turn to budget.

Importantly, the cost of having the same application running on separate codebases is best reserved for the most well-financed projects where native performance may truly be the defining characteristic of the user experience.

Flutter is Google's UI toolkit for building beautiful natively compiled applications for mobile, web, and desktop from a single codebase. Flutter works with existing code and is used by developers and organizations all around the world.

There are many advantages of Flutter as a cross platform mobile development framework, including the ability to create web applications that have a native look and feel on both Android and iOS devices, reduced development time and costs, and increased flexibility.

With Flutter's built-in hot reload feature, developers can easily iterate on their apps and see changes in real-time.

Similar to React and React Native, Flutter is free and open source. You can use it to build apps for Android, iOS, web, and desktop from a single codebase. There are no licensing fees or costs associated with using Flutter.

Benefits of Flutter App Development

If you're looking for a fast, beautiful, and performant mobile app, then Flutter is the best choice. Additionally, if you need to reach a global audience, Flutter is an ideal option as it supports internationalization. In terms of software development, Flutter has a number of benefits that make it a great choice for businesses and developers alike. Let's take a look at some of the key benefits of Flutter app development.


  • Flutter is fast: In terms of software development, time is money. Flutter's hot reload feature means that you can make changes to your code and see the results in real-time, without having to restart your app. This can save you a lot of time and frustration during the development process.
  • Flutter is beautiful: One of the biggest selling points of Flutter is its material design widgets. These widgets give your app a sleek, modern look that is sure to impress your users.
  • Flutter is performant: With its use of the Dart programming language, Flutter apps are compiled ahead of time which means they run faster and smoother on devices.
  • Flutter is international: As mentioned before, Flutter supports internationalization which is vital if you want to reach a global audience. With Flutter, you can easily create an app that is available in multiple languages.

Flutter's Headless Testing Framework

Inside Flutter, there is a headless testing framework that allows you to test your app on devices without a UI. This is great for automating the testing of your app.

How the Headless Testing Framework Works

The headless testing framework is based on the dart:ui library. This library provides low-level access to the Flutter engine, including rendering, gestures, and animations. The headless testing framework uses this library to drive a test suite on a device without a UI. To do this, the framework starts up a minimum number of widgets—just enough to create an isolate—and then executes the test suite. The tests have access to all the same APIs that they would have if they were running in a normal app.

The headless testing framework is ideal for automating the testing of your app because it doesn't require a simulator or emulator. This means that you can run your tests on real devices, which makes it easy to catch errors that only occur on specific devices or configurations. Plus, because the tests are run in isolation, they're very fast—you can easily run thousands of tests in just a few minutes.

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Hot Reload Feature in the Flutter Framework

An hot reload feature that enables you to quickly see the results of your code changes without having to restart the app. The main benefit of hot reloading is that it helps you to iterate quickly on your code changes.

For example, if you're working on a new feature and you want to see how it looks on an actual device, you can make the change in your code and then immediately see the results in the simulator or emulator. This saves you time because you don't have to restart the app every time you make a change.

Experiment More

Another benefit of hot reloading is that it allows you to experiment with different UI designs or implementations without having to start from scratch each time. For example, if you're trying out a new design for a button, you can simply make the change in your code and see the results immediately. By using this, you can save time because you don't have to start from scratch every time you want to try something new.

Faster Development

Without needing to restart the app, you can quickly see the results of your code changes. This significantly speeds up your development workflow as you don’t have to go through the compiling process each time. For bigger projects, this can save you a lot of precious time.

Catch Errors Sooner

And of course, hot reloading can also help catch errors sooner. If you make a change in your code that causes an error, you will be able to see the error immediately in the emulator or simulator. This can help you to debug your code quicker and improve your overall workflow.

Fewer Errors

Another advantage of hot reload is that it helps prevent errors that can occur when making changes in multiple files simultaneously. With hot reload, any errors that do occur are quickly fixed and you can resume working on your project without losing your place. This is a huge time-saver compared to restarting the app each time an error occurs.

Mobile application development with Flutter

Flutter Widgets

One of the benefits of using Flutter is that you have access to a wide variety of pre-built widgets that you can use in your app. This saves you valuable time and resources that would otherwise be spent on developing custom widgets from scratch.

Popular Widgets for Flutter Developers

There are host of widgets available to flutter developers. Let's take a look at some of the most popular widgets in the Flutter widget library:

  • Cupertino Action Sheet - The CupertinoActionSheet widget is a pre-built widget that enables you to quickly create iOS-style action sheets. It supports features such as title, message, and cancel buttons.
  • Material Button - The MaterialButton widget is a pre-built button widget that adheres to the Material Design guidelines. It supports features such as elevation, ripple effect, and text labels.
  • FlatButton - The FlatButton widget is similar to the MaterialButton widget but does not have an elevation property. This makes it ideal for use cases where elevation is not required, such as in dialogs or cards.
  • MaterialApp - A Material Design specific widget that creates an application environment. It builds upon a WidgetApp by adding material-design specific functionality.
  • Scaffold - A Material Design specific widget that provides structure for pages by implementing the Drawer, AppBar, and FloatingActionButton.
  • AppBar - A Material Design specific widget that is typically placed at the top of an app using the Scaffold's appBar property.
  • Drawer - A Material Design specific widget used to create an area where users can navigate to different parts of the app. It is placed within the Scaffold's drawer property.
  • FloatingActionButton - A Material Design specific widget that is used to create a button that 'floats' above other content in the app. It is usually placed in the bottom right corner of the screen using the Scaffold's floatingActionButton property.
  • CupertinoApp - A Cupertino specific widget that creates an application environment similar to MaterialApp but with support for gestures and features from iOS such as CupertinoTabScaffold and CupertinoNavigationBar .
  • CupertinoPageScaffold - A Cupertino specific widget mainly used as a content holder which supports page navigation between subpages using a tab bar at the bottom of the page like in iOS apps .
  • CupertinoNavigationBar -A Cupertino specific widget used to create a navigation bar similar to the one found in iOS apps .
  • CupertinoTabScaffold -A scaffold where selected tabs navigate between subtrees
  • CupertinoTabBar - An iOS style tab bar layout typically placed at the bottom of a screen within a CupertinoTabScaffold.


Flutter offers a rich set of Material widgets and Cupertino components. The Flutter team built the Cupertino widgets to present a UI that looks familiar to iOS users. They had to, because Flutter renders the components itself, instead of relying on the native platform components. Some applications might use only Cupertino, and some might go solely for Material UI. However, what is best is to present a UI that meets Users' expectation, that is:  dynamically use one theme or the other, depending on the platform.

These stateless widgets only update if their inputs change, making them very efficient, while stateful widgets can call the setState() method to update an internal state and redraw.

Flutter Mobile Apps Perform Better

One of the things that sets Flutter apart from other frameworks is its use of the Dart programming language. Dart is a client-optimized language that supports Ahead-of-Time (AOT) compilation. This means that code can be compiled into native machine code, rather than interpreted by a virtual machine at runtime. This results in faster performance and shorter development times.

Dart also features a number of important language constructs that are beneficial to a flutter team, such as:

  • Static type annotations. By adding type annotations to your variables, you can catch errors early and prevent runtime type errors.
  • Isolates. Isolates provide a way to run computation in parallel so that long-running tasks don't block the UI thread.
  • Streams. Streams enable asynchronous programming and make it easy to work with data that arrives over time.
  • Futures.: Futures represent asynchronous computations that will complete at some point in the future.

Dart is a client-optimized language which means that it has been designed specifically for use in web applications. It is also one of the few languages that support Ahead-of-Time (AOT) compilation. AOT compilation means that code can be compiled into native machine code, rather than interpreted by a virtual machine at runtime. This results in faster performance and shorter development times.

Why Use AOT Compilation?

AOT compilation has a number of advantages for mobile development, including:

  • Reduced build times: AOT compilation reduces build times by avoiding the need to interpret code at runtime.
  • Increased performance: AOT-compiled code runs faster because it doesn't need to be interpreted by a virtual machine at runtime.
  • Better debugging information: With AOT compilation, debugging information is available at compile time, which helps you catch errors early.
  • Smaller app size: AOT-compiled code is more compact because it doesn't include a virtual machine or an interpreter.

Dart is Also Used in Native Applications

Dart can also be used to develop native applications for iOS and Android. This is possible thanks to the Dart platform and its accompanying tooling. The Dart platform allows developers to write code that will run natively on both iOS and Android devices.


The use of Dart across different platforms provides several benefits, including but not limited to:

  • Consistent coding experiences across different platforms
  • Code reusability
  • Easier maintenance
  • Shorter development times


These language constructs make it easier to catch errors early, avoid blocking the UI thread, and work with data that arrives over time. As a result, Dart can help you improve your mobile development workflow and build high-quality apps faster.

Flutter can be used Cross Platform and for Web Applications

Understanding What is Flutter

Better understanding what is flutter will help your mobile application development decisioning. Building apps that work across different screen sizes is important because it allows your app to be used by a wider range of people. Not everyone has the same size screen, so it's important to make sure your app can be used by as many people as possible.

Additionally, building an app that works across multiple screen sizes can make it easier to reach a global audience, as people in different regions are likely to have different screen sizes and specifications. Creating an app that works across all screen sizes is key to maximizing its usability and appeal.

Android Studio and VS Code

Google released Flutter in 2017 as an open-source framework for cross-platform app development. The goal of the project was to provide a way for developers to create high-quality, natively compiled apps for both Android and iOS from a single codebase.

The Flutter team at Google currently builds and maintains support for Android Studio (which is based on IntelliJ-IDEA), and Visual Studio Code (VS Code). Android Studio is the official Integrated Development Environment (IDE) for Android app development, based on IntelliJ IDEA. It offers flutter developers a rich set of features that includes support for building mobile apps for Android devices. Visual Studio Code is a code editor redefined and optimized for building and debugging modern web and cloud applications. It comes with built-in support for Flutter development.

Flutter Framework

The Flutter framework uses Android Studio as its official IDE for developing Flutter applications. Android Studio offers developers a rich set of features that includes support for building mobile apps for Android devices. Moreover, it comes with built-in support for the Flutter SDK and its associated tools. This makes it easier for flutter developers to create high-quality, natively compiled apps for both Android and iOS.

Android Studio

Android Studio is the official IDE for developing Android applications, while Visual Studio Code is a code editor that can be used for various programming tasks. Android Studio offers flutter developers a rich set of features that includes support for building mobile apps for Android devices.

VS Code

Visual Studio Code, on the other hand, comes with built-in support for Flutter development. This makes it a better choice for those who are looking to develop cross-platform applications using the Flutter framework.

Is Flutter a frontend or backend?

Flutter uses the Dart programming language, a modern, object-oriented language created by Google. Through its support for native and web development, as well as its use of powerful tools like the Flutter SDK, App Engine, and Firebase, Dart makes it easy to quickly build high-quality mobile apps with Flutter.

Flutter is made as a cross-platform SDK that can be used to build frontend and backend applications in a variety of programming languages, including Dart, Java, C/C++, and more. Its powerful framework and tools make it easy to quickly build high-quality mobile apps for any purpose.

Evolution of the Flutter Framework

There are some major differences between Flutter 2 and 3—namely web support and faster startup times. If you're looking to create an app that will run in a web browser, then you'll need to use Flutter 3. But if you're planning on creating a traditional mobile app, either version will work fine.

Flutter 2.0

Flutter 2 was released back in December 2020 and brought with it some amazing new features like Add to App, NestedScrollView, Slider, and WebView. With Add to App, developers can add Flutter screens to existing apps written in Java, Swift, or Objective C.

NestedScrollView enables developers to create scrollable lists inside of other scrollable lists (i.e., a list inside of a list). And with Slider, developers could create sliders that adapt automatically to the user's screen size.

Lastly, WebView makes it possible to embed web content inside of a Flutter app without having to write any additional code.

Flutter 3.0

The biggest change in Flutter 3 is the addition of support for web apps. That's right—with Flutter 3, you can now create apps that will run in a browser! This is made possible by the new Hummingbird project which uses Dart 2.7 to compile Flutter code into JavaScript.

Flutter 3 expands available platform targets to include macOS and Linux desktop app support, fully integrates Flutter with Firebase, adds native development support for Apple Silicon, and includes numerous productivity and performance features.

In addition to web support, Hummingbird will also enable faster startup times and smaller app sizes.

Other new features in Flutter 3 include:

  • A new text editing controller that improves text input on mobile devices
  • Better support for right-to-left languages
  • Improved maps support
  • New Material Design widgets
  • A range of bug fixes and performance improvements

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React Native vs Flutter

Another popular cross-platform mobile development framework is React Native. Like Flutter, React Native enables developers to create applications that look and feel native on Android and iOS devices. Additionally, React Native has a large community of developers and a large library of components and modules that make it easy to build complex apps.

The two most popular cross-platform mobile development frameworks are Flutter and React Native. Both frameworks have their own pros and cons, but what is the difference between them?

Flutter is a relatively new framework that was created by Google, whereas React Native has been around for a few years now. Because it is new, Flutter is not as widely adopted as React Native yet. However, Flutter has a lot of potential and is growing in popularity.

Flutter uses the Dart programming language, which is different from the JavaScript that React Native uses. Dart is easy to learn for developers who are already familiar with JavaScript.

Flutter apps have a native look and feel on both Android and iOS devices, thanks to Flutter's use of the Cupertino widgets. React Native apps, on the other hand, can sometimes look like they are not quite native on either platform.

Flutter has a built-in hot reload feature that allows developers to see changes in real-time, which is very useful for iterating on an app quickly. React Native does not have a built-in hot reload feature, but there are third-party libraries that provide this functionality.

Overall, both Flutter and React Native are great choices for cross-platform mobile development. It really comes down to personal preference as to which one you choose.

Xamarin versus Flutter

Should I use Xamarin?

Xamarin is a cross-platform mobile development framework that enables developers to create native Android and iOS apps from a single codebase. Xamarin works with the existing code and allows developers to reuse their existing C# skills and code to build high-quality native apps.

There are many advantages to using a cross-platform mobile development framework like Xamarin, including faster development times, reduced costs, and the ability to easily scale an app across multiple devices. Additionally, Xamarin has a large community of developers and a wide range of tools and resources that make it easy to create complex apps.

Flutter and Xamarin are two popular cross-platform mobile development frameworks. While both offer many of the same benefits, such as the ability to build apps that run natively on Android and iOS devices, they each have their own unique set of features and advantages, similar to what React Native will offer.

Compared to Xamarin, Flutter is a newer framework that is built and maintained by Google. It offers a number of powerful features, such as support for Material Design widgets and hot reload, which enables developers to quickly see changes in real-time as they are made. Additionally, Flutter apps are usually smaller in file size than those developed using Xamarin.

One advantage of using Xamarin is that it is compatible with a larger number of platforms, including Windows and macOS. Xamarin also has a large community of developers and a library of reusable components and modules, which can make development easier.

Again just like React Native vs Flutter, which framework you choose ultimately depends on your specific needs and preferences. Both Flutter and Xamarin are great options for building high-quality, highly performant mobile apps that work across multiple platforms.

We would lean more strongly toward Flutter but if you have an application built in Xamarin you may as well continue to maintain it. If we were building for a new application we would recommend Flutter.

Drawbacks of Using Flutter

Overall, Flutter is a great choice for cross-platform software development thanks to its many features and benefits. However, there are also some disadvantages to using Flutter that you should be aware of before choosing this framework for your next app project.One of the main drawbacks of using Flutter is that there can be a lack of available third-party plugins, which can limit the capabilities and flexibility of your app. Additionally, it can be more difficult to hire developers who are familiar with Flutter compared to other frameworks like React Native or Swift.

Another drawback of using Flutter is that it is still a new framework, which means that there is less documentation and support available compared to more established frameworks. Additionally, because it is new, there may be more bugs and glitches compared to other frameworks.

When to Use Flutter?

Flutter is used by developers and organizations to quickly build native mobile applications that look great and perform well on both Android and iOS devices. Its powerful framework allows for faster development cycles, simpler code sharing across platforms, and the creation of highly customized user experiences with ease. Whether you are building a prototype or a complex app, Flutter makes it easy to get started.

1. When You Need Your App Fast Or You’re Developing An MVP

The main difference between Flutter and other cross-platform development platforms is that it allows you to develop apps much quicker. Not only is it a cross-platform SDK, but it also includes the builder tool, as well as numerous user interface components. As a result, building applications quickly becomes possible. It's important to note that while Flutter is still in beta, the framework is fairly stable.

2. When Beautiful User Interfaces Are Important To Your App’s Success

Flutter uses Material Design for its user interface widgets. As a result, your app will look natural on both Android and iOS devices. If you’re looking to create an app with pixel-perfect graphics, Flutter is the platform for you.

3. When Your App Needs High Performance Or Custom User Interfaces

When it comes to performance and graphics capabilities, Flutter delivers. With features like fast rendering, a flexible layout system, and fluid animations, your app can run smoothly with high-end visuals that users love. Additionally, because Flutter is designed to support custom user interfaces, you can create a truly unique experience for your users.

4. When You Want To Reach A Global Audience

Flutter supports internationalization, which means that your app can be easily translated into different languages. This is especially important if you’re looking to reach a global audience or if your app is location-based and will be used in different countries. Overall, Flutter makes it easy to build high-quality mobile apps that run on multiple platforms with ease. Whether you’re a developer or an organization looking to create a new app, Flutter is the right choice for you.

Some notable examples of apps built with Flutter include:

  • Google Ads (Utility)
  • BMW
  • Alibaba (eCommerce)
  • Birch Finance (Finance)
  • Hamilton Musical (Entertainment)
  • Reflectly (Lifestyle)
  • Coach Yourself (Health & Fitness)
  • Spacechat (Social Networking)

Conclusion

Overall, there are both advantages and disadvantages to using Flutter. However, the advantages far outweigh the disadvantages for Flutter app development. We think Flutter is a great choice for cross-platform mobile app development. If you’re looking for a fast, reliable, and flexible framework, look no further than Flutter. At Azumo we are a leading nearshore software development company and can help you build for mobile, web, data and cloud as an outsourced software developer.

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