Windows application development services

 Web |  Mobile |  Cloud

App development services for robust, user-friendly desktop applications built specifically to run on Windows devices.
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We are Your Partner in Windows Development. Modernisation, Greenfield, Legacy Support.

At Assemblysoft, we're equipped to help you navigate the complexities of choosing the right technology for your Windows application development project.

Assemblysoft are Microsoft Certified Developers

Assemblysoft is fantastic to work with! They're always there when you need them, communicate really well, and make everything super easy. From the beginning to the end, they've been an awesome partner. The team's passion for what they do creates a positive vibe that makes working with them a breeze. I highly recommend Assemblysoft for their great service and commitment to making customers happy. Definitely a five-star experience!

James Smith ( Project Lead at MADC LIMITED )

Partner with us as your safe pair of Windows application development hands Microsoft Azure Developers
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experienced with, experts at, well versed in, adept at, battle hardened with Console applications, Windows Services, .NET MAUI, Blazor Hybrid, UWP XAML (Windows.UI.Xaml), Win32 (MFC or ATL), Windows Forms, WinUI 3, WPF

Despite the rapid shift of businesses of all scales towards enterprise cloud-based digital solutions, there is a persistent demand for custom Windows applications.

Windows Apps Customised for Your Business

Our team is committed to delivering high-quality, future-proof applications that meet your specific needs, leveraging the right technology to provide the best user experience and performance.

Rich User Experience

Leveraging the power of native Windows features, these applications deliver a rich and intuitive user experience, enhancing user satisfaction and engagement.

Long-term Support

Windows applications benefit from Microsoft's long-term support, including regular updates and patches, contributing to a secure and stable software environment.

Broad Compatibility

Designed to operate on the Windows platform, these applications enjoy broad compatibility across a wide range of hardware, ensuring accessibility and performance for all users.

Cost-Effective Deployment

Windows applications can be more cost-effective to deploy and maintain, especially for businesses already entrenched in the Windows ecosystem, reducing the need for additional infrastructure investments.

Advanced Performance Capabilities

Taking full advantage of the underlying Windows OS, these applications offer advanced performance capabilities, ensuring efficient processing and responsiveness even in demanding scenarios.

Offline Access

Windows applications provide reliable offline access, ensuring that critical business functions remain available without an internet connection, boosting resilience and continuity.


End-to-end encryption and security best practices, ensuring your data remains safe at all times and adheres to compliance standards for your business domain.

Advanced Performance Capabilities

We develop applications that take full advantage of the underlying Windows OS, these applications offer advanced performance capabilities, ensuring efficient processing and responsiveness even in demanding scenarios.

Windows Forms development considerations


Windows Forms is the original platform for managed Windows applications with a lightweight UI model and access to .NET or the .NET Framework. It excels at enabling developers to quickly get started building applications, even for developers new to the platform. This is a forms-based, rapid application development platform with a large built-in collection of visual and non-visual drag-and-drop controls. Windows Forms does not use XAML, so deciding later to rewrite your application to WinUI 3 entails a complete re-write of your UI.


 Supports C# and Visual Basic, making it accessible for a broad range of developers.

 Drag-and-drop UI designer simplifies form creation.

 Hot Reload support.


Does not natively support Fluent Design.

Limited to Windows platform with no cross-platform development capabilities.

 At Assemblysoft we have developed many WinForms applications and know how to get the best performance for your users.

WPF (Windows Presentation Foundation) development considerations


WPF is a well-established platform for managed Windows applications with access to .NET or the .NET Framework, and it also uses XAML markup to separate UI from code. This platform is designed for desktop applications that require a sophisticated UI, styles customization, and graphics-intensive scenarios. WPF development skills are similar to WinUI 3 development skills, so migrating from WPF to WinUI 3 is easier than migrating from Windows Forms.


 Supports C# and Visual Basic, making it suitable for a wide developer audience.

 Drag-and-drop UI designer and hot reload for streamlined UI development.

 Supports Fluent Design through additional libraries.


Primarily for Windows development with no built-in cross-platform capabilities.

 At Assemblysoft we have real world experience delivering WPF applications that are still supporting businesses like yours.

WinUI 3 development considerations


The Windows UI Library (WinUI) 3 is the latest user interface (UI) framework for Windows desktop apps, including managed apps that use C# and .NET, and native apps that use C++ with the Win32 API. It is still under very active development, so while it might not be able to meet all your needs today it's maturing with every release.


 Modern UI framework that supports Fluent Design.

 Hot Reload for efficient UI development.

 Integrates well with the Windows App SDK.


No drag-and-drop UI designer.

Limited to Windows, with no direct support for cross-platform development.

 At Assemblysoft we can help you develop a WinUI 3 windows application that can support your business with a robust and fluent design.

Win32 (MFC or ATL) development considerations


Win32 desktop apps (also sometimes called classic desktop apps) are the original app type for native Windows applications that require direct access to Windows and hardware. This makes this the app type of choice for applications that need the highest level of performance and direct access to system hardware.


 Offers deep integration with the Windows operating system.

 Supports C++ and Rust, ideal for high-performance applications.


No built-in support for Fluent Design or .NET.

Lacks a drag-and-drop UI designer and hot reload capabilities.

 At Assemblysoft we started out writing pure Win32 and then naturally progressed to (Microsoft Foundation Classes) MFC application development. We can help you maintian or modernise your MFC apps.

UWP XAML (Windows.UI.Xaml) development considerations


The Universal Windows Platform (UWP) provides a common type system, APIs, and application model for all devices in the Universal Windows Platform. Not only can you use UWP to create desktop applications for Windows PCs, but UWP is also the only supported platform to write a single native universal app that runs across Xbox, HoloLens, and Surface Hub. UWP apps can be native or managed.


 Full support for C#, C++, and Visual Basic.

 Drag-and-drop UI designer available.

 Hot Reload for UI debugging.

 Fluent Design System support through WinUI 2.


Limited to Windows platform, no cross-platform capabilities.

Sandboxing might limit certain types of integrations and functionalities.

 At Assemblysoft we have developed Silverlight and UWP (Universal Windows Platform) applications for our clients. We can help you maintain or modernise your existing UWP applications.

Windows App Development Company with over 25 years developing for the Windows Platform

Based in the United Kingdom, with developers spread across the globe, primarily Western Europe, US and Canada.

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