Important
Essential Flutter interview questions that are frequently asked and cover critical concepts every Flutter developer should know.
39
Easy Questions
54
Medium Questions
10
Hard Questions
Easy Questions (39)
Difference between flutter and react native?
flutternative
Flutter difference between (debug , release , profile )build
flutter
Flutter Difference between async , await , future ?
flutterasyncfuture
What is keys in flutter and when to use key in flutter ?
flutter
What is the null coalescing operator ? Ans: '??' to provide "" as a default value.
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Difference between refresh-token and access-token in the Rest API?
api
What is the use of WillPopScope?
navigationwillpopscopepopscopeandroidback-button
What is inherited widget in flutter and what are all the use cases of it
flutterwidget
why you choose riverpod , then bloc , provider what is the difference between them ?
blocriverpodprovider
In kotlin what is the difference between work manager , alarm manager , background services ?
What is the difference between isolates and compute ?
What is difference between using final vs get inside the class where to use which ?
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What is the difference between normal constructor vs Factory constructor proviide me with some real world example ?
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What is the difference between using navigator 1.0 vs navigator 2.0 ? why flutter brought navigator 2.0 ?
flutter
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What is the difference between using DI using getIt vs Using Di from riverpod ?
riverpod
what is the use of entity in flutter difference between using entity and models ?
flutter
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is websocket and webhook is same ? if not then difference between them ?
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What is the use of static vs final vs const ? in flutter when to use which ?
flutter
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What is Dart and Why does Flutter use it?
dartflutterbasics
Write a function to check if a given string is a palindrome. Implement solutions for: (a) Case-sensitive, (b) Case-insensitive, (c) Ignoring spaces and special characters.
algorithmstringpalindromedarttwo-pointer
Write a function to generate the first N Fibonacci numbers. Implement both iterative and recursive solutions and explain the time complexity of each.
algorithmrecursioniterationdynamic-programmingfibonacci
Write a function to reverse a string in Dart. Implement at least 3 different approaches and compare their performance.
algorithmstringreversedarttwo-pointer
What is the difference between dependencies and dev_dependencies in pubspec.yaml?
flutterdartpubspecdependenciespackages
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What is the difference between required, optional, and named parameters in Dart?
dartfunctionsparametersrequirednamed
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Why does the first Flutter app build take so long?
flutterbuildgradlexcodecompilation
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What is the difference between main() and runApp() in Flutter?
flutterdartmainrunAppentry-point
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What frame rate in a Flutter app is good?
flutterperformancefpsframe-rateoptimization
Medium Questions (54)
Lifecycle of stateful widget and explain everything
widgetstate
Diff btw stateless and stateful widget and explain
widgetstate
Flutter is single thread or multi thread
flutter
Flutter method channel vs event channel
flutter
Flutter Hot restart and Hot reload
flutter
Flutter How MVVM Architecture will looks like ?
flutterarchitecturemvvm
What is streams and how to use streams in flutter and what is types of stream in flutter ?
flutterstream
Diff between flutter widgetBinding and MicroTask? And architectural flow diagram how they renderer?
flutterdartmicrotaskevent-loopfuture
What is OWASP security standards ? list down and explain the top 10 stds ?
securityowaspmobile-securityencryptionauthentication
How do you handle performance optimization - app size, rendering speed, and load time?
performance
how to securely store the access token , refresh token or any key in android , ios device ?
androidios
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How flutter secure storage plugin stores the key in both android and iOS ?
flutterstorageandroidios
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why you choose go router then the navigator 2.0 ? what are all the additional functionality go router have then the navigator 2.0 ?
routego_routernavigatornavigation
What is the difference between Widget Tree vs Element Tree vs Render Object Tree in Flutter?
flutterarchitecturewidget-treeelement-treerender-object
The manuall way of publishing apps to app store and play store ?
comparing to native android app , flutter app startup time is very high why how to reduce it ?
flutternativeandroid
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What is the difference between MVC, MVP, clean architecture and MVVM Architecture Pattern? and when flutter officially support mvvm architech why you choose clean architech over mvvm ?
flutterarchitecturemvcmvvmmvp
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What is sound null safety?
dartnull-safetytype-system
What is the difference between NetworkImage and Image.network in flutter?
widgetimagenetworking
Difference between string interpolation vs elvis operator vs force unwrap vs late init provide me with some example in flutter ?
dartnull-safetyoperatorsstring-interpolationelvis-operator
Given a list of integers and a target sum, write a function to find two numbers that add up to the target. Return their indices. If no such pair exists, return null.
algorithmhash-maptwo-sumdartarray
Implement binary search algorithm in Dart. Include both iterative and recursive versions. What are the prerequisites for using binary search?
algorithmsearchingbinary-searchdartdivide-conquer
Implement a Stack data structure in Dart with operations: push, pop, peek, isEmpty, and size. Use it to check if parentheses are balanced in an expression.
data-structurestacklifodartbalanced-parentheses
In Riverpod state management, which provider should I use and when? What are Provider, FutureProvider, NotifierProvider, AsyncNotifierProvider, and StreamProvider? When should I use Riverpod annotations (@riverpod)? What are Mutations in Riverpod 3.0?
riverpodstate-managementproviderasyncnotifiernotifier
In Flutter, when using a StatefulWidget, if the device orientation changes (for example, from landscape to portrait), and we want the video to continue playing from the exact same duration, which lifecycle method of the State class should be used to handle this?
lifecycleorientationstate-managementvideo-playermediaquery
In BLOC, what is the difference between BlocBuilder, BlocListener, and BlocConsumer? How to use them with examples along with BlocProvider and MultiBlocProvider?
blocstate-managementblocbuilderbloclistenerblocconsumer
Real-world StatefulWidget lifecycle scenarios: 1) Inside widget if setState is called, which lifecycle method is called - didUpdateWidget or didChangeDependencies? 2) App is running and device theme changes (light/dark mode), which lifecycle method is called? 3) Device orientation changes, which lifecycle method? 4) Stream data updated, which lifecycle method? 5) State management (BLOC/Riverpod) state changes, which lifecycle method?
lifecyclesetStatethemeorientationstream
Abstract Class vs Concrete Class and Abstract Method vs Concrete Method
abstract-classconcrete-classabstract-methodoopdart
Dart & Flutter Control Flow and Conditional Rendering Techniques
dartfluttercontrol-flowconditional-renderingswitch
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What is the lifecycle of an Android application?
androidlifecycleactivityoncreateonresume
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What will be the output of the following dart code? implements vs extends — difference between using it in class constructors and methods
dartoopsextendsimplementsinheritance
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Explain clearly about immutability vs mutability in flutter with some proper examples
dartflutterimmutabilitymutabilityconst
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Explain clearly about Deep Copy (Hard Copy) vs Shallow Copy (Soft Copy) in flutter with some proper examples
dartflutterdeep-copyshallow-copystate-management
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Explain clearly about difference between deactivate vs dispose in lifecycle of stateful widgets in flutter with some proper examples
flutterlifecyclestateful-widgetdeactivatedispose
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How to remove the duplicate items in the list without using any built in methods like (contains, toSet(), where, indexOf) in flutter with some proper examples
dartdsalistduplicatesalgorithm
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Explain clearly on Skia vs Impeller rendering engine in flutter with some proper examples
flutterskiaimpellerrenderingperformance
Explain clearly on difference between flutter web vs other web development
flutterwebreactseoperformance
When using local database SQLite in Flutter, what is the difference between INNER JOIN vs LEFT JOIN?
fluttersqlitesqflitedatabasesql
What is the difference between Ephemeral State and App State in Flutter?
flutterstate-managementephemeral-stateapp-statesetState
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What is the difference between async and async* in Dart?
dartasyncstreamfuturegenerator
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What is the difference between Adaptive and Responsive design in Flutter?
flutterresponsiveadaptivelayoutmediaquery
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What is the use of Network Inspector plugin in Flutter? Provide examples.
flutternetworkingdebuggingdevtoolsdio
How to activate Flutter DevTools and how to check memory leaks?
flutterdevtoolsmemorydebuggingperformance
How to check jank in Flutter and how to avoid it in future?
flutterperformancejankfpsoptimization
What is the difference between precacheImage and CachedNetworkImage in Flutter?
flutterimagescachingperformanceprecache
Hard Questions (10)
Clean Architecture
architectureclean-architecturedesign-patterns
What is the difference between Abstract Class vs Interface Class vs Final Class vs Sealed Class?
dartoopabstract-classinterfacefinal-class
Flutter Native Integration & Platform Configuration Files
native-integrationplatform-channelsandroidiosgradle
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What is reverse engineering? How to reverse engineer any app in Flutter? How to protect against reverse engineering in Flutter apps?
securityreverse-engineeringobfuscationcertificate-pinningapk
What is the difference between MQTT and WebSocket?
fluttermqttwebsocketiotreal-time
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What is the difference between TDD (Test-Driven Development) vs DDD (Domain-Driven Design) vs DDD (Data-Driven Development)?
tddddddomain-driven-designdata-driventesting
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Step by Step Guide to Embed a Flutter Screen Inside a Native Android App (Add-to-App)
flutterandroidadd-to-appnative-integrationmethod-channel
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When the user says the Flutter app is draining a lot of battery, what to do? How to analyse proactively, how to avoid it, and how to debug it?
flutterbatteryperformanceoptimizationdebugging
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Provide a step-by-step guide to implement a Flutter screen when a user presses a button in a native Android app (Add-to-App).
flutterandroidnativeadd-to-appplatform-channel