When you sit down to play a board game with friends, rule disputes often arise — is a move allowed, how many points for a combination? In a mobile version, there should be no such disputes: every move and every score is controlled by code. We take a board game and formalize its rules as a finite state machine, eliminating any ambiguity. Below I'll explain how we do this and what stack we use. Our mobile board game development services include implementing AI opponents and Firebase multiplayer.
A finite state machine is an abstract machine that can be in one of a finite number of states.
Wikipedia
Formalizing Rules
The first step is to write a complete specification of the rules as a State Machine. For a game like Monopoly or Ludo, that's dozens of states and transitions. We use the State pattern or the Stateless library (ported to Unity). Each transition includes guard conditions and actions. This guarantees: you cannot transition to an invalid state, all rules are explicitly coded, and testing is done via unit tests of states without running Unity.
Here's what the core logic looks like in Swift:
enum GameState {
case waitingForPlayers
case playerTurn(Player)
case resolvingMove
case gameOver(winner: Player?)
}
struct Game {
var state: GameState
mutating func apply(action: Action) -> Bool {
switch (state, action) {
case (.waitingForPlayers, .startGame):
state = .playerTurn(.first)
return true
// ... remaining transitions
default: return false
}
}
}
AI Opponent
For perfect-information games (chess, checkers, abstract strategy), we use Minimax with Alpha-Beta pruning. Search depth depends on the game's branching factor. On mobile devices, we limit search time: if the AI doesn't find a move within 500ms, we take the best found so far. For imperfect-information games (cards, hidden moves), we use Monte Carlo Tree Search (MCTS). MCTS doesn't require an evaluation function and models random factors. On an iPhone 14, MCTS with 10,000 iterations completes within 200ms.
Firebase Multiplayer Setup
For online mode, we use Firebase Realtime Database. The board state is stored as JSON, and client observers synchronize via the Transaction API for atomicity. We configure security rules so each player can only update their own data. Detailed documentation is available in the official Firebase guide.
Choosing an AI Opponent
- Determine the type of information: if all state data is available to both players (checkers, Go) — use Minimax. If there's hidden information (cards in hand) — use MCTS.
- Estimate the average game depth: Minimax is efficient with a small branching factor (up to 30-40 moves). For large branching factors, MCTS is better.
- Test performance on target devices: try both methods and choose the best accuracy-to-speed ratio. For example, on an iPhone 14, Minimax can achieve 6-ply depth within 500ms, while MCTS runs 10,000 iterations in 200ms.
Get a consultation on your project — we'll assess complexity and propose the optimal solution.
Why MCTS Is Better Than Minimax for Imperfect-Information Games
MCTS models random factors without a priori knowledge, whereas Minimax requires a complete evaluation function. For card games, MCTS is 3× more accurate in move selection because it accounts for card draw probabilities.
Multiplayer: Local Pass-and-Play
The simplest and most underrated mode: one phone, multiple players taking turns. Implementation is trivial, but the conversion to organic sharing is high. Add a "pass the phone" screen with a flip animation — and local multiplayer is ready.
For online mode in board games, Firebase Realtime Database is optimal: the board state as a JSON object, observers on both clients. The Transaction API guarantees atomic updates — no race conditions during simultaneous moves.
Comparison of AI Methods
| Method |
Information Completeness |
Performance |
Applicability |
| Minimax |
Perfect |
4-8 ply depth in 500ms |
Chess, checkers |
| MCTS |
Imperfect |
10,000 iterations in 200ms |
Cards, hidden moves |
Work Process
| Phase |
Description |
Estimated Time |
| Analysis |
Rule specification, state definition |
1-2 weeks |
| Design |
Architecture, stack selection |
1 week |
| Implementation |
Coding, AI, multiplayer |
2-6 months |
| Testing |
Unit tests, beta testing |
2-4 weeks |
| Deployment |
Publishing to App Store and Google Play |
1-2 weeks |
Timelines: a classic board game without AI — 2–4 months; with AI and online multiplayer — 4–7 months. Development cost typically ranges from $5,000 to $20,000 depending on features.
What's Included
- Source code with comments and documentation.
- Build and publishing configurations (code signing, provisioning profiles).
- Firebase setup, analytics integration.
- Assistance with app store review.
We have been specializing in mobile development for over 5 years and have completed 20+ game projects. We guarantee quality and on-time delivery. Contact us to assess your project — order turnkey mobile board game development, and we will propose the optimal solution.
Learn more about State Machine on Wikipedia and about MCTS on Wikipedia.
How to choose cross-platform development: Flutter, React Native, or KMM?
We often work with startups that need two apps—iOS and Android—with a budget for one team. Or corporations that want to release an internal tool in three months on both platforms. Cross-platform development solves a specific economic problem: one codebase instead of two. The question is not 'cross-platform or native'—it's 'which tool for which task.'
Each framework dictates its own stack and imposes limitations. An incorrect choice leads to rewriting the project in six months—we've seen it many times with clients who came to us after a failed first attempt. Therefore, before starting, we conduct an audit of technical requirements and team expertise. With 8+ years of cross-platform experience and 50+ delivered apps, we know the pitfalls firsthand.
The three main players now: Flutter, React Native, and Kotlin Multiplatform Mobile. They solve different problems and are poorly compared head-on. Below, we'll break down how to choose the best option for your project.
How do we choose the technology? 4 steps
-
Requirements analysis — list of native APIs, need for offline work, branded UI or standard.
-
Team assessment — expertise in Dart, JavaScript/Kotlin, availability of an iOS developer.
-
Proof-of-concept — implement a critical scenario on the chosen stack in 2–3 days.
-
Final decision — based on performance benchmarks and maintenance cost.
Case from our practice: a fintech startup needed an MVP on both platforms in 10 weeks. Their team had deep React experience, so we selected React Native. The app passed App Store and Google Play review on the first submission, and they launched on schedule. That choice saved 4 weeks compared to training for Flutter.
Comparison of Flutter and React Native: under the hood
Rendering model
Flutter renders UI independently via the Impeller engine (replaced Skia starting with version 3.10). The platform only provides a canvas—Flutter draws every pixel itself. This means:
- Pixel-perfect on all platforms. The same widget looks identical on iOS and Android—good for branded apps, bad if you need a 'native' look on each platform.
- No dependency on OS version. Material 3 in Flutter works the same on Android 8 and Android 14. System Android components are not involved.
- Platform channels for native code. Access to camera, Bluetooth, NFC—via
MethodChannel or EventChannel. flutter_camera, flutter_blue_plus are wrappers over platform channels.
React Native uses native platform components. <View> on iOS is UIView. <Text> is UILabel. This means:
- Native look and feel without extra effort.
- New Architecture (Fabric + TurboModules) with JSI removed the JSON bridge between JS and native code. Synchronous calls work without serialization. This is critical for animations and gestures.
- React Native Reanimated 3 runs worklets on the UI thread—animations at 60/120 fps without blocking the JS thread.
Performance in practice
For most business apps, the performance difference between Flutter and React Native New Architecture is imperceptible. The difference appears in edge cases.
Flutter is slower when interacting with platform APIs via platform channels—each call is asynchronous, with data serialization overhead. google_maps_flutter renders the map via PlatformView—a native UIView/View embedded in the Flutter tree. Before Impeller, this caused performance issues (Hybrid Composition vs Virtual Display). With Impeller, Flutter renders UI 2–3x faster on low-end devices compared to Skia, and PlatformView performance improved by 40%.
React Native is slower in scenarios with heavy JS logic on the main thread. Parsing large JSON, complex computations—these block the JS thread and appear as UI freezes. Solution: Hermes (JS engine optimized for RN) + offloading computations to a native module or react-native-workers. With Hermes, cold start time is reduced by 30–40% compared to JavaScriptCore—that's 2x improvement on older devices.
Ecosystem and maturity
| Parameter |
Flutter |
React Native |
| Language |
Dart |
JavaScript / TypeScript |
| Package manager |
pub.dev |
npm / yarn |
| Major companies |
Google, Alibaba, BMW |
Meta, Microsoft, Shopify |
| Hot reload |
Yes (stateful) |
Yes (Fast Refresh) |
| Desktop (macOS, Windows) |
Yes (stable) |
Experimental |
| Web |
Yes (CanvasKit / HTML) |
Partial (via React) |
| APK/IPA size |
~6 MB base |
~4 MB base |
Dart is a barrier to entry for teams with a JS/TS background. It's possible to learn basic Dart in a week, but shifting your mindset to Flutter widgets and widget tree takes longer.
TypeScript in React Native is the de facto standard. A team with React experience becomes productive faster.
When to choose Flutter?
- Need a unified branded UI on all platforms (iOS, Android, Web, Desktop).
- Team is ready for Dart.
- Lots of custom animation and custom UI—Flutter is more predictable.
- The app is not tied to specific native APIs.
When to choose React Native?
- Team has React/TypeScript expertise.
- Need native look and feel.
- Heavy use of native components (Maps, Camera with native capabilities).
- Sharing code with React web via monorepo.
Kotlin Multiplatform Mobile: a different story
KMM solves not a UI problem, but the problem of business logic duplication. The concept: write business logic, networking, caching, validation once in Kotlin. iOS receives a .framework via Kotlin/Native, Android uses the library directly. UI on each platform is native.
// Shared Kotlin code — works on iOS and Android
class UserRepository(
private val httpClient: HttpClient, // Ktor
private val database: AppDatabase // SQLDelight
) {
suspend fun getUser(id: String): User {
return database.userQueries.selectById(id).executeAsOneOrNull()
?: httpClient.get("$BASE_URL/users/$id").body<User>().also {
database.userQueries.insert(it)
}
}
}
Ktor — HTTP client for KMM (works on iOS via Darwin engine, on Android via OkHttp). SQLDelight generates a typesafe Kotlin API for SQLite, works on both platforms.
Real limitations of KMM
Coroutines on iOS: suspend functions from shared code are called through automatically generated wrappers. SKIE (Swift/Kotlin Interface Enhancer) from Touchlab significantly improves the Swift interface: async/await instead of callbacks, AsyncStream for Flow. Without SKIE, working with coroutines from Swift is inconvenient.
Compose Multiplatform: JetBrains is developing Compose for iOS — UI in Compose works on iOS via Metal. This blurs the line with Flutter: one Compose code for both platforms. Status today: Beta, with early adopters in production (Touchlab, JetBrains own products), but stability is lower than Flutter.
Complexity of iOS integration: XCFramework from KMM module is added to an Xcode project. SPM integration exists and works. But iOS developers must understand the Kotlin API and memory management rules via Kotlin/Native (ARC + Kotlin GC work together, which is not always obvious).
When KMM is justified
The company already has mature iOS and Android teams that duplicate business logic. Switching everything to Flutter or React Native is too radical. KMM allows starting small: extract networking and models into shared code, keep UI native. Gradual migration without rewriting everything.
Typical mistakes in technology selection
Choosing Flutter "because it's a single codebase" for an app heavily reliant on native APIs (custom camera, BLE, background processing). Implementing these via platform channels adds complexity that eats up the development speed advantage.
React Native without understanding the JS thread. Heavy operations on the JS thread cause visible freezes. This is solvable, but requires understanding the architecture—otherwise the app will perform worse than native.
KMM without an iOS developer on the team. Shared Kotlin code requires an iOS engineer who integrates the framework into Xcode, writes SwiftUI on top of KMM APIs, and debugs Kotlin/Native crashes.
What is the development process and timeline?
A cross-platform project goes through the same stages as a native one: requirements audit → stack selection → design → development → testing on real devices of both platforms → publication in App Store and Google Play → support.
Testing on real devices is not optional. An emulator does not reproduce memory issues on budget Android phones and does not show differences in gesture behavior on iOS. We test 40+ scenarios on at least 5 real devices covering both OS versions.
| Project Type |
Flutter |
React Native |
| MVP (8–12 screens) |
7–12 weeks |
7–12 weeks |
| Medium (20–30 screens) |
3–5 months |
3–5 months |
| Complex (native integrations, AI) |
5–8 months |
5–8 months |
Budget savings compared to two native teams can be up to 40–50%. The cost is calculated individually after analyzing the stack and requirements.
What's included in our work
- Technical audit and stack selection for your project.
- Architecture design (clean architecture, MVVM, BLoC/Redux).
- UI development according to design mockups for both platforms.
- Integration of native modules (camera, geolocation, push notifications).
- CI/CD setup (GitHub Actions, Codemagic).
- Testing on real devices (iOS/Android) — at least 40 scenarios.
- Preparation and publication in App Store and Google Play following guidelines (App Store Review, Google Play Policy).
- Technical support for 3 months after launch.
- Handover of source code, documentation, and access — all turnkey.
We'll evaluate your project in one day—get a consultation on stack selection. Order turnkey development and receive a cross-platform app within the agreed timeline, backed by our experience and guaranteed milestones.