Kotlin Multiplatform: Android, iOS, Desktop & Web - One Codebase

Kotlin Multiplatform 2025: The Year It Went Mainstream

From Google's endorsement to Compose iOS going stable, 2025 was the year KMP transitioned from emerging technology to industry standard. Here's everything that happened.

The Transformation Is Complete

At the start of 2025, we predicted this would be the year Kotlin Multiplatform went mainstream. Looking back now, that prediction was conservative. What actually happened exceeded even our optimistic expectations.

KMP is no longer experimental. It's no longer a "wait and see" technology. It's a proven, production-ready platform backed by Google and JetBrains, with hundreds of companies shipping apps to millions of users.

Q1 2025: The Foundation Year

Compose Multiplatform for iOS Hit Stable

The biggest milestone of the year happened in March: Compose Multiplatform for iOS graduated to Stable. This wasn't just a version number change – it was JetBrains' official stamp of approval for production iOS development.

Companies that had been waiting on the sidelines immediately started migrating. By Q2, we saw a 300% increase in iOS projects using Compose Multiplatform compared to the previous quarter.

Tooling Consolidation Paid Off

JetBrains' decision to focus on IntelliJ IDEA and Android Studio proved brilliant. The concentration of resources meant:

  • Faster bug fixes and feature releases
  • Better integration with existing Android workflows
  • Smoother onboarding for Android teams adding iOS support

Android Studio Meerkat's KMP templates became the standard way to start new projects, making setup trivial for new teams.

Q2 2025: The Swift Revolution

Kotlin-to-Swift Export Changed Everything

May 2025 brought the game-changer: direct Kotlin-to-Swift export went public. The impact was immediate and dramatic.

iOS developers who had been skeptical about working with "Android code" were suddenly enthusiastic. Shared Kotlin code appeared in Xcode as natural Swift APIs with:

  • Swift optionals instead of Objective-C nullability annotations
  • Value types and structs for data classes
  • Full generic support without type erasure
  • Named parameters that felt native

The developer experience transformation was so significant that several companies reported their iOS teams preferring to work with the shared code over writing platform-specific Swift.

SwiftPM Integration Sealed the Deal

Along with Swift export came Swift Package Manager integration. iOS developers could now add shared code as a package dependency, just like any other Swift library. No CocoaPods configuration, no manual framework imports – just add a package and start coding.

Q3 2025: Web Platform Maturity

Kotlin/Wasm Reached Beta

September marked another major milestone: Kotlin/Wasm promotion to Beta. WebAssembly support became production-ready, and early adopters reported impressive results:

  • Near-native performance in browsers
  • Smaller bundle sizes compared to Kotlin/JS
  • Better debugging experience
  • Seamless integration with existing web apps

Compose for Web Caught Up

Compose Multiplatform for Web also reached Beta in Q3. This meant teams could finally share their Compose UI code across Android, iOS, Desktop, and Web from a single codebase.

The multithreading support prototype that JetBrains showcased allowed web apps to leverage multi-core processors, bringing desktop-class performance to browsers.

Q4 2025: The Enterprise Adoption Wave

Google's Jetpack Expansion

Throughout 2025, Google steadily added KMP support to more Jetpack libraries. By year-end, we had:

  • Room, DataStore, Collection (stable since 2024)
  • ViewModel, SavedState, Paging (added early 2025)
  • WorkManager (beta in Q3)
  • Navigation (beta in Q4)
  • Security and Biometric libraries (announced for 2026)

Each library addition reduced the amount of platform-specific code developers needed to write, pushing typical code reuse percentages from 60-70% to 75-90%.

Production Success Stories Exploded

2025 saw a flood of production case studies:

  • Major E-commerce: Several large retailers shipped KMP apps, reporting 50-65% development cost savings
  • Financial Services: Banks and fintech companies chose KMP for security-critical applications
  • Media Companies: News organizations and streaming services rebuilt mobile apps with KMP
  • Startups: Hundreds of new startups launched with KMP-first architecture

By December 2025, an estimated 30-40% of new Android-first companies were choosing KMP for their iOS strategy, exactly as we predicted.

The Numbers Don't Lie

Adoption Statistics

Looking at the data from 2025:

  • Developer Survey: 73% of respondents had used or experimented with KMP in production (up from 60% in 2024)
  • Job Market: KMP job postings increased 400% year-over-year
  • App Stores: Over 5,000 apps in the App Store and Play Store disclosed using KMP
  • GitHub: KMP-related repositories grew 250%

Cost Savings Reality Check

Companies shipping KMP apps in 2025 reported actual numbers:

  • Average code reuse: 78% (up from 60-70% in 2024)
  • Development cost reduction: 45-70%
  • Time-to-market improvement: 40-60% faster
  • Bug reduction: 35% fewer bugs from eliminating duplicate logic

A typical mid-sized app that would have cost $500k with separate teams cost $200-250k with KMP – and shipped 3-4 months faster.

What Actually Happened vs. Our Predictions

In early 2025, we made four specific predictions. Here's how they played out:

  1. Prediction: 30% of new Android-first companies will choose KMP by Q2
    Reality: 35% by Q3 ✓ (Better than expected)
  2. Prediction: Major e-commerce platforms will announce KMP adoption by Q3
    Reality: Three major retailers announced in Q2-Q3 ✓
  3. Prediction: At least one KMP app will reach #1 on both App Stores by Q4
    Reality: Two apps hit #1 in their categories ✓
  4. Prediction: 100+ KMP jobs posted weekly by year end
    Reality: 150+ weekly by November ✓ (Exceeded)

The Challenges We Faced

2025 wasn't perfect. The ecosystem faced real challenges:

iOS Build Times

Kotlin/Native compilation remained slower than ideal. While JetBrains made improvements throughout the year, full iOS builds still took 2-3x longer than equivalent Swift compilation. Teams adapted by investing in CI/CD infrastructure and using incremental builds more effectively.

Learning Curve for iOS Teams

iOS developers needed to learn Kotlin, and while Swift export helped enormously, the initial ramp-up still took 2-4 weeks for experienced developers. Companies that invested in proper training saw much faster adoption.

Debugging Complexity

Debugging shared code across platforms remained trickier than single-platform development. The tooling improved throughout 2025, but cross-platform debugging still required more expertise than traditional native development.

Unexpected Wins

Some developments in 2025 surprised us:

Desktop App Renaissance

We underestimated how attractive desktop development would become. Compose Multiplatform's desktop support, combined with the ability to share code with mobile apps, sparked a genuine desktop app renaissance. Companies built:

  • Internal business tools sharing logic with mobile apps
  • Developer utilities with native performance
  • Creative software alternatives to Electron apps
  • Companion desktop apps for mobile services

The Flutter Migration Wave

Mid-2025 saw something unexpected: companies migrating from Flutter to KMP. Teams cited reasons like:

  • Desire for truly native UI instead of custom rendering
  • Preference for Kotlin over Dart
  • Better integration with existing Android codebases
  • Google's official support

The Education Sector

Universities and coding bootcamps rapidly adopted KMP in their curricula. By year-end, over 200 institutions worldwide were teaching KMP, creating a pipeline of KMP-ready developers entering the job market.

What We Built at Prospat in 2025

It was an incredible year for us. We:

  • Shipped 12 production KMP apps for clients
  • Trained over 300 developers in KMP development
  • Migrated 5 existing apps from separate codebases to KMP
  • Established best practices and architecture patterns
  • Built open-source libraries used by the community

Our clients achieved an average of 55% development cost reduction and shipped 45% faster than their previous projects.

Looking Ahead to 2026

2025 proved KMP is production-ready and mainstream. 2026 will be about:

  • Refinement: Better tooling, faster builds, improved debugging
  • Ecosystem Growth: More libraries, more platforms, more integrations
  • Enterprise Scale: Fortune 500 companies going all-in on KMP
  • Web Maturity: Kotlin/Wasm and Compose for Web reaching stable
  • New Platforms: Expanding to wearables, embedded systems, and IoT

The Bottom Line

2025 was the year Kotlin Multiplatform transitioned from "emerging technology" to "industry standard." The pieces didn't just fall into place – they locked together:

  • Google's official endorsement ✓
  • Compose iOS reaching Stable ✓
  • Direct Swift export ✓
  • Mature tooling ✓
  • Thriving ecosystem ✓
  • Proven production success ✓

The question is no longer "Should we consider KMP?" It's "Why aren't we using KMP yet?"

At Prospat, we're excited to continue helping businesses leverage KMP in 2026. We've seen firsthand how it transforms development teams, reduces costs, and accelerates time-to-market.

Ready to make 2026 your KMP year? Let's discuss how we can help you build better apps faster.

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