For most of the last decade, "cross-platform" effectively meant React Native or Flutter. Kotlin Multiplatform (KMP) changed that quietly, and the adoption numbers moved fast: JetBrains' Developer Ecosystem survey put KMP usage at 7% in 2024 and 18% in 2025, and a Snapp Mobile survey found 46.7% of respondents interested in exploring it further. That is a real shift, not a rounding error.
It is also not a reason to switch. The two tools solve overlapping problems in genuinely different ways, and the right answer depends far more on your team and your product than on any benchmark. Here is a tool to get you to a starting position, followed by the reasoning behind it.
What the two actually do
This is the distinction most comparisons skip, and it matters more than any performance chart.
React Native shares the whole app. Your UI and your logic are both JavaScript or TypeScript, rendered through real native platform components. One codebase produces the screens your users touch on both platforms.
Kotlin Multiplatform shares the logic, not the UI. You write your business logic, networking, data layer and validation once in Kotlin, then build the interface natively on each platform — SwiftUI on iOS, Jetpack Compose on Android. (Compose Multiplatform can share UI too, but the common starting point is shared logic with native UI.)
That single difference drives nearly everything else. React Native optimises for one team shipping one thing to two places. KMP optimises for keeping native UI quality while removing duplicated logic.
The five factors that decide it
1. Who is on your team, and who will you hire next?
This is the factor we see decide more projects than every technical consideration combined. JavaScript and React form the largest talent pool in software; a web engineer becomes productive in React Native quickly because the language, component model and package manager are the same ones they already use.
KMP asks for Kotlin plus, realistically, some Swift and Android know-how — because you are still building two native UIs. If you already have native mobile engineers, that is a strength, not a cost. If you are a web-first team or a startup that needs to staff flexibly, it is a real hiring constraint.
2. How much does native UI fidelity matter?
If your product lives or dies on feeling perfectly at home on each platform — the exact navigation transitions, the platform-native text selection and accessibility behaviours, every new OS design refresh on day one — KMP's native-UI model gives you that by construction, because the UI genuinely is native.
React Native composes real platform components, so it inherits most of this by default, but a strict design system across both platforms still takes deliberate work.
3. Are you adding to an existing native app, or starting fresh?
KMP is unusually good at incremental adoption. You can extract one module — say your pricing rules or your sync layer — into shared Kotlin and leave the rest of both apps untouched. For a company that already has two mature native apps and is tired of fixing the same bug twice, that is a compelling, low-risk path.
Starting from zero with no native codebase and no native team, that advantage largely disappears, and React Native's single-codebase model gets you to a shipped product faster.
4. How deep is your ecosystem dependency?
React Native draws on the entire npm ecosystem plus a deep bench of maintained native modules — payments, maps, biometrics, camera pipelines, the long tail — and Expo has turned cloud builds, store submission and over-the-air updates into solved problems rather than CI projects.
KMP's library ecosystem is younger. For mainstream needs it is fine, and you can always drop to native for anything platform-specific, because you are writing native UI anyway. The practical test: list the five hairiest integrations on your roadmap and check both ecosystems for maintained packages before you commit. Twenty minutes of checking beats any comparison article, this one included.
5. Is a web app part of the same product?
If your product has a significant web surface, React Native lets you share types, API clients, validation logic and sometimes whole business-logic layers between web and mobile, with one hiring pool covering both. That is a compounding advantage that has nothing to do with rendering performance.
Where we land, and why
We build in React Native. The honest reason is the hiring and maintenance argument above, not a benchmark: one talent pool, one codebase, one release train, and a fix that lands once and ships to both stores.
That is a preference formed by the kind of work we do — products going from zero to launched, usually with a web surface alongside. If you have two mature native apps and a native team already on payroll, the calculus genuinely changes, and KMP deserves a serious look. A team that only ever recommends its own stack is not giving you advice.
A reasonable way to decide
Score these honestly rather than arguing about frameworks in the abstract:
- Count the mobile engineers you have and can hire in the next year, by language.
- Write down whether you are starting fresh or adding to existing native apps.
- List your five hardest integrations and check library support in both.
- Decide whether a web surface shares logic with mobile.
- Ask whether native UI fidelity is a core product value or a nice-to-have.
If four of five point the same way, you have your answer. If they split, pick the one your team can staff and maintain — that is the tiebreak that still looks right in three years.