Flutter Vs Uno Platform - Which Is The Better Cross-Platform Development Platform

Flutter vs Uno Platform

When it comes to building a mobile app or web application in today’s times, the first thought is naturally about which app development tool you should use. With the prolific use of multiple platforms like Windows, Google Android, Apple iOS, and Web/WebAssembly, cross-platform development has emerged as the best platform for app development.

The latest statistics also support cross-platform development, with the global market set to cross $7.9 billion in 2021. To improve their market reach, companies are now adopting hybrid frameworks to develop their apps instead of sticking to a native framework.

This has led to a plethora of cross-platform development frameworks to choose from for application developers. Let’s take a look at what cross-platform development is and how Uno Platform performs when compared to Flutter.

Here is what we will cover in this article,

  • What is Cross-Platform Development?
  • What is Uno Platform?
  • What is Uno Platform used for?
  • Pros or Advantages of Uno Platform
  • Cons or Limitations of Uno Platform
  • What is Flutter?
  • What is Flutter used for?
  • Pros or Advantages of Flutter
  • Cons or Limitations of Flutter

What is Cross-Platform Development?

By definition, cross-platform development is the framework used to build applications that can run on multiple platforms including Android, iOS, Web, macOS, Linux, and Windows. Why is cross-platform development so popular? Here, application developers only need to write the application code once and then deploy it across platforms. This removes the hassle and inefficiency of creating multiple versions of your app-specific to each platform.

How does this benefit your business? First, it saves a lot of time and money spent on application development, thanks to the single code base. Second, businesses can now reach out with their apps to a wider customer base using different devices or operating systems.

On the flip side, however, cross-platform development can restrain your app performance as it cannot leverage the native capabilities or features of specific platforms. 

To get a better understanding, let us evaluate two of the best cross-platform development frameworks available in the market – Flutter and Uno Platform. Let us look at each of their pros and cons, and how they compare to each other in terms of popularity, performance, ease of learning, and so forth.

What is Uno Platform?

Developed in 2013 (and open-sourced in May 2018), the Uno cross-development platform is another open-source framework that is used to build single-source applications to run on WinUI / Universal Windows Platform (or UWP)-based, Android, iOS, WebAssembly, Linux, and macOS. Using the Uno Platform, developers can write their code once using C# and XAML – and then compile the code base for multiple platforms.

Uno Platform can tap into native UI frameworks used in individual platforms, thus making the final application work like a native app.

What is Uno Platform Used For?

Uno Platform is widely used for creating pixel-perfect applications for cross platforms on Web, desktop, and mobile devices. 

Thanks to its integration with Microsoft WinUI that is based on XAML, Uno Platform developers can leverage WinUI's styling engine to deliver pixel-perfect apps. Uno Platform has been widely used by companies like Air Canada, Cineplex, and VCA to develop their cross-platform apps.

Next, let us look at the pros and cons of using the Uno framework.

Pros or Advantages of Uno Platform

Listed below are some of the pros (or advantages) of using the Uno framework:

Single-source code everywhere

Among the biggest differentiator from other frameworks, you can now write your application once (using C# and XAML) and then deploy it on any target platform.

Faster UI Changes

With its “XAML Hot Reload” feature, you can modify the XAML code on any running application operating on iOS, Android, and WebAssembly. This enables faster app iterations from UI changes, making them more efficient and productive.

100% reuse

With Uno Platform, Windows developers with C# and XAML coding experience can now reuse their knowledge of WinUI, UWP, and Silverlight tools. Additionally, Uno Platform application development is supported on MS Visual Studio, Visual Studio Mac, Visual Studio Code, and JetBrains Rider for all supported platforms.

Pixel-Perfect Rendering

Uno Platform delivers a consistent and pixel-perfect look to its apps on all platforms, by using the UWP/WinUI 2D directives for all UI elements. With Uno Platform, you can use native buttons for iOS and Android to deliver a platform-specific look to native apps.

Uno Platform gallery and playground

Speed up your app development on multiple platforms with the collection of Fluent and Material code snippets from the Uno Platform gallery. Additionally, you can use the Uno Platform playground to create new (or edit existing) code snippets and test them live on any browser.

Cons or Limitations of Uno Platform

Along with its many pros, Uno Platform also has its share of limitations (or cons), as listed below:

Reuse of UWP APIs

Uno Platform reuses the existing APIs from UWP. This is in contrast to Xamarin.Forms that created new abstraction APIs for its underlying use.

Limited user base

As Uno Platform became open source only in 2018, it has a smaller user base along with limited API support and third-party support.

What is Flutter?

Developed and released by Google in 2018, Flutter is an open-source and cross-platform application development framework. This UI-driven tool has been used to create a variety of applications for mobile devices, desktops, web, and embedded devices – all using the same code base.

Among app developers, Flutter is known for developing native-like applications with matching performance on most modern devices and platforms.

What is Flutter Used For?

As the platform-independent technology from Google, Flutter has been extensively used for creating web, mobile, and desktop applications across popular platforms. Developed using the Dart programming language that is in turn created from Java, Flutter is an open-source development framework that has been used to create popular applications like Google Ads, Google Pay, eBay, Dream11, and more.

On its part, Flutter offers an easy way of developing visually appealing applications for both the web and the desktop using a single code base.

Next, let us look at the pros and cons of using the Flutter framework.

Pros or Advantages of Flutter

What makes Flutter so popular among app developers? Let us look at some of its pros (or advantages):

Faster app development

Thanks to its “Stateful Hot Reload” feature, you can utilize its rich set of customizable widgets to build customized web interfaces within minutes. Additionally, you can complete code changes and observe the real-time changes on any device – in real quick time.

Expressive UIs

The combination of the Dart language and Skia rendering engine allows Flutter developers to create high-quality applications with expressive designs. Other built-in Flutter features like the Material Design and Cupertino widgets, rich APIs, and natural scrolling add to the rendering of expressive app UIs.

Enhanced native performance

Using the Dart native compiler, Flutter code can be easily compiled into any native ARM machine code. Flutter applications perform at the same level as native apps as this framework does not depend on any intermediate code interpretation. Plus, Flutter widgets imbibe each of the native platform features and differences in scrolling, navigating, fonts, and icons.

Easy to learn

As Flutter is derived from Java and Dart languages, it is easier to learn as compared to other cross-platform frameworks. The growing online community of Flutter developers enables you to learn from them using online learning resources.

Cons or Limitations of Flutter

Along with its many pros, Flutter also has its share of limitations (or cons), as listed below:

Lack of third-party native libraries

Flutter has limited support for third-party native libraries to be integrated into this framework. It is still possible to include native libraries into Flutter, but that process can be long and time-consuming.

Not suited for smaller apps

Most Flutter applications are still larger than their native counterparts, thus making this framework unsuitable for smaller or progressive web apps. Additionally, Flutter applications consume up to 20MB in memory usage.

Developing augmented (or virtual) reality apps

Flutter is not the preferred choice for building AR or VR apps on multiple devices. There are plenty of alternate tools that support more AR/VR devices, faster app development, and support.

Flutter vs. Uno Platform: Which is Better?

Having looked at the differences between Flutter and Uno Platform, here are some criteria that you can use to make a decision as to which one is best for you in your situation. We’ll help you decide using the following criteria:

  • Popularity
  • Performance
  • Learning curve
  • Code reuse
  • Developer community and support


This is one factor where Flutter enjoys an advantage over Uno Platform. The 2020 Developer Survey conducted by StackOverflow showed that nearly 69% of app developers would love to create apps using Flutter. Having said that, Flutter is more favored by Android and iOS developers. On the other hand, the Uno Platform is more widely used by Windows and Linux users with a background in C# and XAML programming.


Uno Platform outperforms Flutter when it comes to performance on selected devices. Here are some of the performance results of both when we tested them on different devices,

On Samsung Note 10 Android phone

The number of updates per second that were recorded was 24,017 on Uno Platform(with SkiaSharp) as compared to a figure of just 12,210 for Flutter. Similarly, the number for just Uno Platform and Uno Platform(with WebAssembly) was recorded at 947 and 640 respectively – while Flutter (with Web) recorded just 9.

On a Desktop computer

On a desktop PC, the number of updates per second that were recorded was 111,762 on Uno Platform(with SkiaSharp) as compared to a figure of just 45,024 for Flutter. Similarly, the number for Uno Platform(with WebAssembly) was recorded at 1927 – while Flutter (with Web) recorded just 20.

Learning curve

How easy (or difficult) is it for a new app developer to learn both these frameworks? The harder the learning curve, the lesser would be the number of skilled coding professionals.

First, let us talk about the Uno Platform. It primarily uses.NET languages like C# that can still be learned and used outside of Uno Platform. This makes it worthwhile for fresh developers to invest in learning this language. Similarly, for .NET developers, the transition from Windows UWP to Uno Platform is smoother. On the other hand, the learning curve for Uno Platform is still difficult as it is a newer technology and does not have a large repository of online learning resources.

When it comes to learning Flutter, you need to invest time into learning Dart language that has limited usage outside the Flutter framework. Additionally, Dart is a newer programming language that has only recently been extended to compile using JavaScript runtime for creating web applications.

Code reuse

For cross-platform development frameworks, code reuse is a significant factor in deciding which framework is better. 

Flutter allows developers to write common code for multiple platforms, but it also has its share of platform-specific differences. This makes code reuse limited in Flutter, as you need to add a lot of code (specific to each supporting platform) to your web application – so that it works smoothly across devices.

With Uno Platform, you can reuse between 95-98% of application code (including the UI elements) to deliver the same user experience across platforms.

Developer community and support

Are you looking for strong developer community support where there are ample learning resources and developer forums? Despite Flutter’s higher popularity score, Uno Platform compares favorably when it comes to developer community support and documentation.

Flutter has a larger developer community, but most of them are based in Asia (so there could be a language barrier in some countries).

On the other hand, the Uno community is active with closer to 4,000 members from all over the globe. Most of the posted questions are answered in under 15 minutes. However, what is concerning is the lack of Uno Platform documentation. Having said that, Uno Platform has the backing of Microsoft's investments into .NET and C# programming languages.

Which one is Better? Flutter or Uno Platform?

Cross-platform development frameworks are a must when you want to host your web apps on multiple platforms to increase your market reach. In this article, we have compared Uno Platform with the more popular Flutter framework in terms of their performance, learning curve, and community support. 

Which is the better development framework for you? The choice between Flutter and Uno Platform is completely dependent on your application and business needs. Using our comparison, you should be able to choose the one that’s best for you. Either way, you’re sure to increase your productivity!