The Ultimate Guide to Flutter Frameworks

Calendar Icon

Publish date:

June 5, 2021

Updated on:

March 11, 2024

Clock Icon

Read time:


The Ultimate Guide to Flutter Frameworks


Flutter is an app development platform that is rapidly evolving to include new features, new targets, and new possibilities for its developers. With the release of Flutter 2.0 last year, the platform is doing more to attract high-quality application developers and expand its capabilities into the future. Multiple surveys reveal that it is projected that Flutter will be one of the most popular technologies for application development in 2023. It is estimated that Flutter will be behind many embedded screen applications, such as those found in vehicles.

The latest release of Google’s cross-platform development tool is already unlocking new potential within development teams. With thorough knowledge and understanding of how Flutter works, how it can deliver an amazing UX performance with tools such as Flutter delays, what it can be deployed to achieve, and why you should use it to improve your organization — you can begin to shape its use and practices to build your applications.

If you need help connecting with Flutter teams, then you can simply tell us what you need. We can do the work for you and connect you with up to 5 companies within 72h that match your needs – for free.

What is Flutter?

Typically, cross-platform frameworks and libraries are compared against each other from a developer’s viewpoint. While this is useful from a technical perspective, when assessing whether to choose Flutter or React Native, for example, it’s not an entirely accurate description of Flutter’s complete capabilities.

It would be more technically accurate to describe Flutter as a Software Development Kit (SDK) rather than a framework. The difference between the two is that Flutter comes complete with all the tools and resources necessary for developers to build cross-platform solutions.

With past experience in Flutter, a fresh download of the SDK, and a suitably outfitted code editor — a developer is equipped with everything they need to begin building applications. Today, Flutter is capable of building for iOS, Windows, Linux, macOS, and web development from just a single codebase and using this single tool.

Of course, Flutter’s unique place in the technology landscape does come with trade-offs that are worth re-evaluating. The most notable of these are the language and architecture differences that make up the foundation of the platform.

These pros and cons of Flutter Development can influence workflows and practices negatively within organizations. While many of the drawbacks are rapidly being addressed or written out altogether, several remain as the technology develops into a more mature solution.

With a community growing at a steady pace and developers gradually getting up to speed with Flutter, there is still a sizeable leap to make to bring the advantages of the tool into existing workflows while leaving out the drawbacks.

On balance, however, these are costs often more than justified by the abundant advantages that go into making Flutter one of application development’s most powerful tools and technologies

Whether you need an outsourced Flutter development team or a single freelancer to bring into your firm, our Flutter interview questions, resources and guides can help you get up to speed with the latest thinking in Flutter development and help you set off on the right path in no time at all.

What Is Google Dart?

Both a significant drawback and notable advantage to Flutter development, Google’s Dart language is often the most polarizing and distinct feature of the platform.

Dart is a language initially developed for internal use at Google back in 2011. It wasn’t until the release of Flutter, however, that the language saw any kind of popularity in the wider community. Now, it’s a language that is slowly and steadily growing over time.

Amongst those developers learning Dart, many have found it to be a hurdle less significant than they’d have imagined. Virtually tailor-made for multi-platform development and founded in the principles and technologies of similar languages, it’s a technology easy to transition to from web or JavaScript development.

Backing by Google comes with significant advantages for the language with abundant available learning resources and tools to assist in making the language a highly productive and effective one within teams.

Flutter’s Architecture

The most distinct and unique thing about Flutter is the architecture and design that makes it such a powerful platform.

The architecture of Flutter can be viewed as a series of interchangeable layers that sit on top of the system the technology is targeting. Each of these layers allows Flutter to abstract application design from the underlying platform to the Flutter framework that can be targeted by developers.

Two people discuss frameworks in front of a whiteboard.

It’s these three primary layers of Flutter that give the technology a “build once, run everywhere” philosophy that is so highly valued.

At the foundation of the platform, the platform embedder runs “close to the metal” and is independently designed for every target platform Flutter runs on. The embedder’s primary role is to provide essential classes and libraries that directly interact with the target system.

The next level of the Flutter hierarchy is the engine responsible for many of the platform’s stand-out features. At the heart of this is the rendering engine powering Flutter’s UI and widgets—something that deserves a second look.

Related components that go into Flutter’s engine include networking, plug-in support, and the runtime files and compiler for the Dart language. The essential systems and libraries that allow Flutter code to be executed before interfacing with the underlying system—via the embedder—are included here.

Interacting with the engine, the topmost layer in Flutter’s architecture is the framework itself. The layer Flutter developers spend almost their entire time writing input into, this layer also provides a convenient shorthand between developers to refer to the Flutter SDK as a whole.

Within this framework layer are the UI widgets, application components, and interfaces that go into constructing a multi-platform application. By necessity, the Flutter framework includes diverging UI components for both Google’s Material Design standard and Apple’s Cupertino design libraries.

Flutter’s layered component style architecture allows applications to stay relatively focused and streamlined in their performance. It allows for the inclusion of only the application components necessary to run the underlying app, excluding the parts they don’t need and won’t use.

Additional features developers may want to lean on, such as a device’s camera or sensors, the web view, in-app payments, and authentication can be added in code modules as required by the Project.

The Unique Advantage of Flutter: Application Rendering

One of Flutter’s greatest selling points is the rendering engine for drawing UI components. As a relatively unique feature of application frameworks, this engine allows Flutter to draw and display its own UI components rather than rely on those from the target system.

This pays off for Flutter in creating a level of detail, control, and runtime performance that few frameworks can match.

The conventional approach to rendering UI elements with an application framework is to create an abstraction layer, or bridge, that translates and makes calls to a system’s native UI libraries. This encourages the target system to do the heavy lifting of rendering animations and components with the drawback of added overhead in the application bridge impacting performance.

In contrast, Flutter minimizes this overhead by bringing with it its own set of widgets for use across every platform. By doing this, Flutter bypasses the UI libraries of the system entirely and can claim up to 120 frames per second rendering performance as a result.

From the perspective of a user, the drawbacks of Flutter’s approach come from unifying buttons and widgets across all platforms. While this makes it easy for apps to look consistent across multiple platforms, it can make apps stand out next to other apps being used on the same platform.

Combining Flutter and Native

Because Flutter departs from a more conventional way of using frameworks and creating cross-platform applications; there are some natural concerns about merging Flutter code into native applications and vice-versa.

Combining the two worlds is more than just a technical demonstration of Flutter’s abilities. Such applications are essential when there’s a significant investment in pre-existing work or unique requirements that can’t be met by any framework. In many cases, a gradual change of an extensive codebase is a better solution than an abrupt interruption or re-design from the ground up.

Flutter solves this issue and creates ways of both including platform-specific views into Flutter apps and importing Flutter components into native apps.

Platform view widgets enable you to import native views into Flutter apps. This solves a tricky multi-platform problem and allows the widget to act as an intermediary between the view and the application.

The converse scenario is achieved with a Flutter module that allows a Flutter application to be embedded inside a parent native app. Included within the module are the engine, shared libraries, and tools that a Flutter app needs to run.

Including everything a Flutter app needs inside the app has a natural trade-off, which is sacrificing outright performance for compatibility. Far from a perfect solution, it’s one that serves as a reasonable intermediate step to accessing Flutter functionality when only a native app will do.

Flutter in Practice

New technologies are inherently exciting and attractive. Brand new solutions make teams want to jump on board at the first chance and take advantage of new trends and cutting-edge tools. Few things in application development should be done lightly, however.

To invest in a new technology or platform, you must prove that this change in direction will provide real, quantifiable value and solutions for the future. There’s no shortage of businesses that have skipped this step to be met only with the drawbacks and disadvantages of Flutter technology.

With Flutter, the value and advantages of the platform are readily demonstrated in its architecture and design. Claims of native-like performance, rapid cross-platform application development, and expressive UIs are justified by the vast departure from more conventional architectures. Favoring an approach that makes fuller use of the technology and the platform, the additional features of Flutter make it worth serious consideration.

There are, of course, drawbacks too. The most significant of which comes with the changes that Flutter makes to implementing layouts and deploying widgets. Changes in how Flutter works will take some time to get developers up to speed. Developers not yet familiar with Dart will require time to learn the deepest features and depths of Google’s language too — a process that turns out to be surprisingly short and simple.

The platform’s all-in-one approach, the decision to include everything the app needs to run internally, also increases the size of the resulting apps. More lightweight native solutions may still be a better approach for applications that require a smaller footprint.

The payoff for investment in the comparatively new platform is new levels of UI customization, a reduction in time-to-market, and abundant code share between competing platforms.

Flutter is one of the most exciting and promising new technologies in modern application development. Here, a person logs onto a laptop to utilise the framework.

Understanding Flutter

Getting to know the ins and outs of Flutter can take a lot of the anxiety and nerves out of investing in the platform. Luckily, learning it in-depth is a lot easier to do than you might imagine.

With a comprehensive understanding of Flutter’s unique architecture and an in-depth knowledge of how, why, and when to use the technology — it’s never been easier to start considering deploying the technology with Flutter development companies to enhance your organization.


Q1. What are the skills required for Flutter?

  • Experience with native languages, platforms, and tools. To be a proficient Flutter developer you should have knowledge and experience in developing for the target platform natively, or with other application frameworks at least. This can help you troubleshoot Flutter issues vs platform issues and provide a more in-depth knowledge
  • Experience using Dart. Flutter’s language for app development, a skilled Flutter developer should be proficient in not just JavaScript but in the details and tools available to Dart too
  • Agile methodologies. Most modern development takes place using agile methodologies while waterfall is considerably less common. Skilled developers should have spent some time using both and know how to adhere to the relevant features in each to ensure the project runs successfully and smoothly
  • SQLite experience. SQLite is essential to most modern frameworks and application development. Flutter provides a lot of tools and resources to support its use in Flutter applications—something proficient developers should be more than capable of taking advantage of

Q2. What does a Flutter developer do?

Flutter developers build cross-platform applications to target mobile platforms, desktop, and the web with highly attractive and interactive applications. Leaning on the tools and capabilities of the unique framework, Flutter developers are able to target this wide array of platforms and functionality from just a single code base.

A proficient Flutter developer will likely have had significant experience designing and building native applications on at least one of the target platforms and a wealth of development experience overall. For this reason, a Flutter developer commonly has a rich portfolio of previously delivered apps and knowledge and experience in software development that would put them in a senior role.

While a developer will spend the vast majority of their time coding applications, a significant portion of a Flutter project will be spent designing, testing, debugging, and delivering the resulting application to the client too.

Q3. Is Flutter a framework or language?

Flutter is most often referred to by developers as a framework. Technically speaking, Flutter is much more in reality and might more accurately be referred to as a software development kit. Because the framework contains everything needed to build and launch an application on its own, it’s technically more than a framework on its own.

Flutter contains the libraries, tools, and documentation to build cross-platform apps in addition to the Dart language Flutter runs on and the ready-to-use code and widgets it relies on.

In practical terms, the uppermost layer of the Flutter architecture that developers target and build towards is the framework itself. The result is that framework is a useful shorthand to refer to the entire Flutter structure as that’s most often the relevant component and also how the tool is evaluated against competing frameworks in the marketplace.


Enjoyed the article?

Like it and let us know what you think, so we can create more content tailored to your interests.

Ian Deed

Linkedin Icon

Software developer, mobile application engineer, and writer helping companies to enhance their tech branding and improve the way they communicate with technical and non-technical audiences.

Leaning on years of experience and knowledge to understand technical communication that works from wordy jargon that doesn't.

More from this author

Join the community.