XForma

XForma is a lightweight .NET UI framework for apps with a custom look that should look the same on every platform, while keeping the platform's own text rendering, text entry and scrolling.

XForma was called XForms until November 2026. It isn't related to Xamarin.Forms or to the W3C's XForms standard.

What makes XForma different

• Native text, custom look. Text rendering (the platform's fonts, shaping and emoji), text entry (input methods, spell checking, selection, accessibility, autofill), scrolling physics and virtualized lists all use the platform's own implementation. Everything else is owner-drawn, so controls look identical everywhere and don't change when a platform's design language does.

  Other frameworks usually pick one side:

  • MAUI and React Native use native controls, so apps look different on each platform.
  • Flutter, Avalonia, Compose Multiplatform and Uno's Skia renderer draw everything, text and text entry included.

  XForma does both: native where quality comes from the platform, owner-drawn everywhere else.

• A small framework, with controls on top. All platform-specific code lives in a small framework. Control libraries, including XForma's own controls, are written once on its public API. The compiler enforces that, so any control library you write runs on every supported platform.

• Your look, not ours. Controls have no look of their own: each lays out and draws from a theme package, and the compiler rejects look that creeps back into a control. Use the Basic theme, adapt it, or write your own.

• No markup or styling machinery. There's no XAML, styling engine or reflection-based binding engine to learn or carry. Views and typed bindings are plain C#.

• Lean. On Windows, XForma uses Win32, DirectComposition, Direct2D and DirectWrite directly, with no XAML or Windows App SDK. Its test app is about 21 MB self-contained and trimmed, compared with about 221 MB for the same app on WinUI 3. The Windows backend uses source-generated interop, so it's trimmable and compatible with Native AOT.

• Native performance. Layout is shared across platforms but driven by each platform's own layout system, and animations run on the platform's compositor, off the UI thread.

Why choose XForma

XForma is a good fit when:

• you want a distinctive, fully custom design that's identical on every platform;
• you also want text and text entry to behave exactly as they do in the platform's own apps;
• you work in C# and prefer a small, understandable stack to a large framework.

It's not the right choice (yet) when:

• you need macOS or Linux today;
• you need a large ready-made control set, a data grid, markup or a designer;
• you need a mature ecosystem: XForma has one developer and one app;
• you want a native look on each platform (consider MAUI), or need to reuse WPF or WinUI XAML (consider Avalonia or Uno Platform).

See docs/comparisons.md for detailed comparisons with Uno Platform, Avalonia, .NET MAUI, Electron, React Native, Flutter and Compose Multiplatform.

Why a custom look?

If you've been shipping apps for more than a few years, you'll know that the "native" look on every platform periodically changes, and apps that once looked sleek and modern now look obviously dated. Not necessarily bad, just dated, because they're using old "native" controls.

I noticed that some old iOS apps in particular still looked great, and the thing they all had in common was a completely custom user interface that still looked and worked great for their scenario.

That's when the light clicked on for me.

Despite how much each platform owner (Apple, Google, Microsoft) pushes you to support their latest native look, so your app looks like every other app and you'll probably have to rewrite it for every platform as well, it may not be your best option.

If you agree that makes sense for your app, then XForma may be just what you need.

How it's organized

Folder	Project	What it is
framework/	XForma.Framework	The platform-neutral framework: app hosting, layout, input, accessibility, popups, and the native primitives
platform/win32/	XForma.Framework.Win32	Windows: Win32, DirectComposition, Direct2D, DirectWrite, RichEdit
platform/android/	XForma.Framework.Android	Android: native views
platform/ios/	XForma.Framework.iOS	iOS: UIKit
platform/web/	XForma.Framework.Web	Browsers: .NET on WebAssembly, DOM elements and canvases
xforma/	XForma	What apps reference: controls (buttons, pickers, calendar, menus, flyouts, lists, ...), panels, gestures, binding and the app's entry point, built only on the framework's public API
themes/	XForma.Themes.Basic	How the controls look: the Basic theme, and the base for your own
toolkit/	XForma.Toolkit	Services for any .NET app: clipboard, preferences, secure storage, sharing, file pickers and more
analyzers/	XForma.Analyzers	Build rules that keep the layers and the look apart
test/	XForma.Test.*, XForma.Tests	Test apps for each platform, with shared pages in test/XForma.Test, and the unit tests

An app references XForma and a theme package. See docs/architecture.md for how the layers, layout, drawing, input, popups and lists work.

Building

Requirements:

• the .NET 10 SDK;
• the .NET Android workload, for Android;
• the .NET iOS workload, and a Mac, to build for and run on iOS.

Build everything with:

dotnet build XForma.slnx

Run the Windows test app with:

dotnet run --project test/XForma.Test.Win32

Status

XForma is working toward 1.0, and its API can still change. Version 1.0 promises four platforms:

Platform	Tested on
Windows (Win32, no XAML)	Windows 11
Android	Emulators
iOS	Simulators
Web (.NET on WebAssembly)	Edge

What 1.0 leaves out is listed in docs/support.md.

Documentation

Start here: getting started, guides for each topic and the API reference.

• Architecture: the layers, and how layout, drawing, input, popups, lists and accessibility work.
• Comparisons: XForma compared with Uno Platform, Avalonia, .NET MAUI, Electron, React Native, Flutter and Compose Multiplatform.
• Alignment: how the API lines up with familiar frameworks, and the history of each phase.
• Support: what 1.0 includes and leaves out, supported versions, and how issues are handled.