MAUI Interview Questions

Interviewers frequently start by testing whether you understand what MAUI actually is: the evolution of Xamarin.Forms into a single project system where Android, iOS, Windows, and Mac Catalyst all live under one .csproj using multi-targeting (<TargetFrameworks>net8.0-android;net8.0-ios;...). A strong answer distinguishes MAUI from Xamarin.Forms by naming concrete improvements — single project structure, .NET 6+ unified BCL instead of Mono-only APIs, and a new handler-based architecture replacing renderers.

A common follow-up asks you to explain Shell navigation versus classic NavigationPage: AppShell.xaml defines a flyout/tab structure declaratively with routes registered via Routing.RegisterRoute, enabling URI-based navigation like await Shell.Current.GoToAsync("//details?id=5") with query parameter passing via [QueryProperty]. Interviewers also probe the app lifecycle events (OnStart, OnSleep, OnResume in the App class, or the newer platform lifecycle events wired through MauiProgram's ConfigureLifecycleEvents) to see if you understand state preservation when an app is backgrounded.

Senior-level interviews probe startup time and trimming: MAUI supports Native AOT compilation and full trimming on iOS/Mac Catalyst (and increasingly Android) to shrink binary size and cut JIT startup cost, but trimming can silently break reflection-based code (like some JSON serializers or DI container internals) unless you annotate types with DynamicallyAccessedMembers or test thoroughly with <TrimMode>full</TrimMode> in Release builds. Another favorite is explaining why CommunityToolkit.Mvvm's source generators (like [ObservableProperty]) are preferred over manually implementing INotifyPropertyChanged — they eliminate boilerplate while keeping runtime behavior identical, without any reflection overhead.