A guide to hiring Xamarin developers
Xamarin is a toolset for building iPhone and Android apps with C# and .NET. Teams used it to share most of their code between the two platforms. Microsoft has since ended support for Xamarin and now points teams to .NET MAUI, so hiring for Xamarin today often means two jobs: keep the current app stable, and plan what comes next. This guide explains what Xamarin developers do, how the role differs from nearby roles and how to set up the work so it goes smoothly.
What Xamarin developers work on
Most Xamarin work falls into four groups. Maintenance covers crash fixes, library updates and changes needed when Apple or Google release a new system version. Features are new screens and flows added to a working app. Integration links the app to your servers, payment tools, maps and sign-in systems. Migration moves the app toward .NET MAUI or another platform. A small team often needs one person for all four, while a larger one splits them.
How this role differs from nearby roles
A Xamarin developer works in C# and shares code across both phone systems. Our iOS developers and Android developers write native apps for one platform each. Our mobile app developers page covers wider mobile work, including Flutter and React Native. Choose this page when your app or your team already uses C# and .NET, or when you need to look after a Xamarin app you inherited.
Xamarin.Forms, native Xamarin and .NET MAUI
- Xamarin.Forms lets you build screens once in XAML and run them on iOS and Android.
- Native Xamarin, with Xamarin.iOS and Xamarin.Android, gives direct access to phone features while still using C#.
- .NET MAUI is the newer path from Microsoft for the same idea, and it is where new C# mobile work is going.
- Some teams move to native Swift and Kotlin instead, which costs more up front but removes the shared layer.
Say early which of these your app uses today. It changes the plan, the tools and the skills you should ask for.
What to decide before you hire
- Whether the goal is to keep the app steady, add features or move to a new platform.
- Which Xamarin version and packages the app uses, and which ones are no longer updated.
- Whether you ship to iOS, Android or both, and who owns the store accounts.
- How the app is built and released today, and whether tests exist.
- How long users can wait for a move, and what must keep working during it.
Reading a Xamarin developer’s profile
Start with apps you can download from a store. Ask which parts the person wrote and what they would change today. If code is public, read it and see whether the history tells a clear story. Treat a long tool list with no recent app work as a warning sign. Ask about a stubborn bug in older code: someone who can retrace how they found the cause has real experience.
Interview questions to try
- How would you find out why an old Xamarin app crashes only on some devices?
- When would you use a custom renderer, and what are the risks of using many?
- How do you keep screens easy to test with MVVM?
- Walk us through how you would plan a move from Xamarin.Forms to .NET MAUI.
- How do you handle a package that is no longer updated by its authors?
Listen for plain answers with examples from real projects. Be wary of anyone who calls a migration easy before seeing the code.
Run a small paid task
Set each finalist a small job close to your real app. Options include reviewing one screen and listing its risks, fixing a known bug in a copy of your code, or building a tiny .NET MAUI sample that calls your API. Pay for the hours. Then compare readability, how the person explains their choices and how they respond to follow-up questions.
Match experience to the stage
If your app is stable and needs light care, a steady mid-level developer who knows the codebase may be enough. If you plan a migration, you need someone who has done one and can write a clear plan. If the app is business critical, ask for a person who can set up tests and builds first, so every change is safer. Titles vary a lot, so ask what each person was responsible for.
Give them tools and a rhythm
Open the repository, the build pipeline and test devices or emulators to your developer, and give store access only as far as the work needs. Keep signing keys and store logins inside your company. Meet weekly during the first month and look at every change together. Later, a brief weekly update and a review before each release is enough.
Working with your wider team
A Xamarin developer works well with a clear owner for the product, a designer who knows phone patterns and a back-end developer for the API. Share bug reports and user feedback early. Keep a short list of known risks, such as old packages and unsupported features, so that nobody is surprised when an update to iOS or Android needs extra work.
Mistakes to avoid
- Leaving an unsupported app untouched until a store update breaks it.
- Starting a full rewrite before reviewing what the current code does well.
- Moving every screen at once instead of in small, testable steps.
- Giving one contractor sole control of signing keys or store accounts.
- Creating the repository or cloud accounts under a contractor’s name.
Need other mobile skills as well? Read about how to hire iOS developers, Android developers or mobile app developers, and see how hiring works on our pages.