Flutter: Promising Framework for Cross-Platform Development

Flutter is a new framework for cross-platform app development, but there’s already a lot of positive noise around it. Many developers name it the best cross-platform SDK ever made. Therefore, we’ve decided to check this out. Let’s discover Flutter’s features and pros and cons of using this cross-platform framework.

In our company, we specialize in cross-platform development, and our chosen framework for years was Ionic (if you’re curious why check “Why Should You Consider Ionic for Your Mobile App?”). But as every developer do, we also continuously look for new tools to build even better, high-performing cross-platform apps. Therefore, we got curious about Flutter – the new cross-platform SDK released by Google. 

Many developers were claiming that it solves cross-platform development issues and is the best cross-platform framework ever made. We’ve decided to do some research and tests to check for ourselves what Flutter is and how can it be beneficial for our clients. No matter if you’re a business owner or a developer, you may discover a lot from our investigation, so check the results!

What is Flutter? Flutter is an open-source, free mobile SDK (Software Development Kit) for cross-platform development, released by Google. It’s a framework with widgets and tools that allows building apps for Android and iOS with only one codebase. One code works on both platforms, and, what’s more, your app looks and acts like a native one, with all the native interface elements. As a result, users don’t feel a difference between a Flutter app and a native app.

Google announced the framework in February 2018 at the Mobile World Congress. Since then, they constantly expand their potential. Flutter gains new powers and Google actively promotes it. Also, the company used it to create a Google Ads app. But what is so extraordinary about Flutter, that would make it better than other frameworks built by giants, like React Native from Facebook or Xamarin from Microsoft?

Cross-platform apps most often have slightly worse performance than native ones. In the case of frameworks like React Native, they need additional “bridge” to access platform widgets, responsible for animations, swiping and transitions. Importantly, the widgets are accessed a lot, and each time the code needs to pass the “bridge”. It results in a slightly lower performance. Although, Flutter has an answer to that issue. 

To create the Flutter app, we need to use a programming language named Dart. It is compiled into native code ahead-of-time, which means, already during the building process. In consequence, it doesn’t need any bridge, and there’s no performance gap. The framework changed everything in the case of the layout. Traditionally, layout determines the position or size of widgets. Developers write rules to determine a widget and these rules interact with each other. As a consequence, they make the app slower. In Flutter, it’s the other way around: almost everything is a widget, and each widget has its own, specified layout model. In consequence, that allows for even better performance. 

Moreover, Flutter provides its own widgets instead of platform ones. And it resolves another problem, connected to creating the same design for each platform quickly and customizing it. With Flutter widgets, apps look the same on each platform. What is more, they look the same on each system’s version. Typically, adjusting the look of the app to the older OS versions requires time and a lot of testing. With Flutter, we can be sure that our app will look perfect, and it may look the same also after the system’s updates.

It’s time, to sum up everything we’ve learned about Flutter into the framework’s advantages and disadvantages to make your decision about trying it out a little bit easier. We are going to present it from two points of view: business owner’s and developer’s one.

Let’s start with the business owner’s perspective. When should you choose this framework to build a mobile app for your company? What to take into account while making a decision?

• With Flutter your developers write literally one code: in most cases, this code can be shared between Android and iOS by 100%. That’s not possible with many popular cross-platform frameworks.
• The SDK is free to use and open-source.
• Flutter apps provide excellent User Experience. It provides a perfect performance. The design looks like in a native app and is constant through all platforms, devices and system versions. Users will appreciate it.
• With Flutter widgets, you can be sure that your app is going to look the same on both platforms. What is more, it will look the same on the older system’s versions as well.
• Flutter widgets allow developers to create a customized design that matches a brand image easily.
• Time for testing is reduced. Your developers write one instead of two codes. The time spent for testing your app on older Android and iOS versions are also reduced thanks to widgets (the app is adjusted already).
• Flutter is perfect for MVP development. It allows you to build an app fast to present it to your investors. The app will look excellent and work on each device they need.

• Dart is the new programming language developers should learn from scratch. The number of companies and developers that had mastered Dart is still low. There are no patterns of writing in this language and not so many tutorials and resources, so the developers need to learn by themselves.
• Google still works on Flutter for the web. At this moment, the framework works only for mobile app development. Although Flutter for the web is available in the beta version.
• Apps are a bit large. Because of the widgets, an app weighs at least 4 MB although they work on changing that.

Now, let’s check out what features of Flutter are essential from a developer’s point of view.

• 100% of the code is shared between iOS and Android platforms.
• Thanks to using Flutter’s widgets, the User Interface looks the same on both platforms: Android and iOS, and also on older system versions. You can be sure that your app is going to look perfect on each platform and OS version. Although, if you want to differentiate your design, it’s possible.
• Developers spend less time on testing the app on the older OS versions. 
• Widgets make design easier. You can create a customized design easily. 
• The testing of various elements is easier because of Hot Reload feature. You can make some changes in code and see it within a few seconds.
• Designers’ work is also easier thanks to Hot Reload. They can preview changes instantly and experiment more.
• The framework has detailed documentation and a supportive community.
• Flutter is open-source, and that makes learning it a bit easier.
• Flutter is easy to set up. You don’t need to worry that your computer won’t be compatible with the framework.

• At this moment, Google works intensively on Flutter for web applications.
• There are not enough materials and tutorials to learn Dart and Flutter easily. You have to do some work by yourself.
• Libraries are still limited. Not every functionality you may need can be found in Flutter’s libraries. As a result, you may need to build it by yourself, which takes a lot of time.

At Appstronauts, we’re really excited about this new and promising framework. Our developers are already testing it, learning how to develop flawless apps with this SDK and becoming masters of Dart. We’ll be delighted to share our thoughts and best practices with your company. If you are looking for a Flutter app development company, just drop us a message about your project at hello@appstronauts.co.