Avalonia vs Expo
Which should you use? A side-by-side look at what each one does, who it suits, what it costs, how hard it is to set up, and where each falls short.
Open source · MIT
A C# and XAML framework for building desktop, mobile and web-assembly UI apps.
Open source · MIT
Open-source framework for building native Android, iOS, and web apps with React.
The short answer
Choose Avalonia if you need…
- C# developers who already know XAML or WPF
- Teams that want one UI codebase across desktop and mobile
- Developers building internal or commercial desktop tools on .NET
- Projects that need to run in a browser via WebAssembly
Choose Expo if you need…
- Developers who want to build iOS and Android apps with React and JavaScript
- Teams that want one codebase covering mobile and web
- People who want to try Expo quickly in the browser via Snack
- Developers who want hosted build and release services through EAS
Side-by-side
| Avalonia | Expo | |
|---|---|---|
| Type | Framework | Framework |
| Price | Free and open source | Free and open source |
| Licence | MIT | MIT |
| GitHub stars | 31.7k | 53.3k |
| Setup difficulty | Intermediate | Intermediate |
| How you get it | Install with a package manager | Install with a package manager |
| Main language | C# | TypeScript |
| Last code update | 4 days ago | 4 days ago |
What each one is
Avalonia
Avalonia is a cross-platform UI framework for .NET. You describe screens in XAML and write logic in C#, and the same app can run on Windows, macOS, Linux, iOS, Android and WebAssembly. The README says it is similar to WPF, so developers familiar with that model should find it familiar.
Expo
Expo is an open-source platform for building apps that run on Android, iOS, and the web, written in React and JavaScript. It includes a universal runtime and a set of libraries so one codebase can produce native apps. The repository also holds the Expo SDK, CLI, Router, Expo Go app, and documentation source.
Best for
Avalonia
- C# developers who already know XAML or WPF
- Teams that want one UI codebase across desktop and mobile
- Developers building internal or commercial desktop tools on .NET
- Projects that need to run in a browser via WebAssembly
Expo
- Developers who want to build iOS and Android apps with React and JavaScript
- Teams that want one codebase covering mobile and web
- People who want to try Expo quickly in the browser via Snack
- Developers who want hosted build and release services through EAS
Strengths
Avalonia
- Runs on many platforms (Windows, macOS, Linux, iOS, Android, WebAssembly) from one .NET codebase
- Familiar model for XAML and WPF developers, per the README
- MIT licensed with an active repository and documented tutorials and samples
Expo
- Covers Android, iOS, and web from a single React and JavaScript codebase
- Large public project with active development and an MIT license
- Has official documentation, a community chat, and a browser-based playground
Not ideal for
Avalonia
- People who want a no-code or visual-only builder, since the README centres on writing C# and XAML
- Developers committed to a non-.NET language stack, since the framework is built for C#
- Anyone needing a WPF app to run unchanged on macOS or Linux, since the README points to a separate commercial product, Avalonia XPF, for that
Expo
- People who only need a website and have no mobile plans, since a simpler web framework may suffice
- Developers who need full control over native code from day one, as the README points to custom native modules as a separate workflow
- Non-programmers, since the project assumes React and JavaScript knowledge
Trade-offs
Avalonia
- Not a 1:1 copy of WPF, so existing WPF code may need changes
- Some features (such as WPF-app porting to macOS and Linux) are in a separate commercial product
- Tooling for live XAML preview varies by IDE; JetBrains Rider needs a third-party community plugin
Expo
- The README is a monorepo overview, so most setup detail lives in external docs rather than here
- Some dependencies use other licenses, such as BSD, per the README
- Some capabilities such as hosted services are provided by EAS, a separate platform
Getting started
Avalonia
Install core Avalonia packages via NuGet Package Manager console
Install-Package AvaloniaInstall the desktop package
Install-Package Avalonia.DesktopFrequently asked questions
What is the difference between Avalonia and Expo?
Avalonia: A C# and XAML framework for building desktop, mobile and web-assembly UI apps. Expo: Open-source framework for building native Android, iOS, and web apps with React. Avalonia suits c# developers who already know xaml or wpf, while Expo suits developers who want to build ios and android apps with react and javascript.
Are Avalonia and Expo free?
Avalonia: Free and open source. Expo: Free and open source.
Is Avalonia or Expo more popular?
Expo has more GitHub stars (53.3k) than Avalonia (31.7k). Popularity isn't the same as fit — check which one matches your use case above.
What are other alternatives to Avalonia and Expo?
Other options people compare them with include React Native, MAUI, Capacitor, Next.js, Razzle.
Keep comparing
Built from our catalogue entries for both products: open-source details come from each project's README (AI-assisted, refreshed weekly) and GitHub data; AI-tool details are editorial. Spotted something wrong? Let us know from either product's page.