Can you build iOS and Android apps with AI at the same time? Ten builders, four mechanisms

Yes, in four ways. Each way produces a different pair of apps and a different codebase in your hands:

One codebase, rendered on both. You write (or the agent writes) one set of screens in JavaScript (React Native, via Expo) or Dart (Flutter); a runtime shipped inside the app renders them on each platform. One prompt produces both apps by construction, and they look and behave identically — because they are the same screens. Platform features reach the app through modules. React Native vs native covers what that runtime can and cannot reach.

One shared core, two native UIs. The behaviour — state, actions, effects — is written once; each platform gets its own user interface in the platform’s own toolkit. Modaal’s Duet docs put it in one line: “you write the views twice and the behavior once.” One project produces both apps; they behave the same and look like their platforms.

Two native apps. Each platform gets its own app in its own language, with its own code. Rork’s docs: “each app has its own code.” The result is two ordinary native projects; keeping them in step is your testing, not the tool’s.

A wrapper for both stores. The app is a web app (or a managed build on the vendor’s platform), packaged as an IPA and an AAB. Base44’s docs: “Your mobile app runs your published Base44 app inside a secure web view.” Both stores from one input, with the limits of a web view.

Replit. “You can build cross-platform apps for iOS and Android from the same codebase.” Preview in the simulator (Core plan and above) or Expo Go; iOS release via TestFlight and App Store Connect; “Publishing to Google Play is not supported through a guided experience yet, but can be accomplished manually.” No Mac needed. Core $20 a month ($18 annual), Pro $100 ($90 annual). Replit alternatives has the wider field.

Bolt. “Expo is a platform that lets you build mobile apps for both iPhone and Android using the same code.” Choose mobile in the first prompt — “Projects created for web do not easily switch over to mobile.” Tokens “roll over and stay valid for two months.”

Anything. “Under the hood, Anything generates Expo (React Native) code.” Pro $19 a month billed annually ($24 monthly); unused credits expire monthly; “Google Play publishing is in beta.” Anything alternatives compares the credit rules.

Vibecode. “Your apps are built using React Native and Expo, which compile to native iOS and Android code.” Credits “roll over each billing cycle and never expire”; the site labels its prices “experimental”.

Emergent. “Supported: Expo/React Native only”; “No Mac needed — EAS builds iOS apps in the cloud.” Standard $20 a month; the mobile agent is on paid plans only.

FlutterFlow. Flutter rather than React Native: “The lib/ directory contains all the Dart code that drives your Flutter app.” Basic at $39 a month adds “Code Download”, “APK Download” and “One-Click App Store Deployment”; the free plan has none of the three.

What you hold afterwards: one JavaScript or Dart project. A React Native or Flutter developer continues it; an iOS or Android developer opens it as a foreign project.

Modaal’s Duet template exists in two flavours, “iPhone and Android together” and “iPhone now, Android later”. From the docs: “Each feature’s logic — its state, the actions that change it, the effects it requests — is written once.” “The iPhone app renders that state in SwiftUI; the Android app renders it in Jetpack Compose.” The two are held in step by the build, not by hope: “Both platforms replay the same fixtures and the gate is byte equality, so a divergence fails the build on the commit that caused it.”

In practice: you describe a feature; your own agent — Claude Code, Codex, Gemini, Copilot or Cursor — writes a plan you approve, then the shared logic and both native interfaces; the result is an Xcode project and an Android Studio project in Git on your Mac. The free plan builds one project on one platform with unlimited prompts, and Android is included in every account; “Building both platforms is a Pro feature” — €9 per user per month billed annually (€15 monthly) — pricing. “You still need a Mac.”

What you hold afterwards: a Swift project and a Kotlin project that iOS and Android developers open as their own, plus one shared core. The trade against group 1: two sets of views to write (the agent writes them), a Mac, and no cloud build. How Duet works has the mechanism in full.

Rork’s docs, read 10 September 2026: “Rork writes a real Android Studio project in Kotlin” and “each app has its own code.” The iPhone app is Swift, the Android app is Kotlin, and they are separate codebases. Whether one prompt produces both apps at once is not stated on the pages we read; plan for building them as two apps. Pro is $20 a month for 100 credits; the free plan is “Design mode” without working code; “Paid users own all generated code. Download it via GitHub!”

What you hold afterwards: two native projects with no shared core, so a change in behaviour is made twice and checked twice. Modaal vs Rork compares the two native routes. Superapp, the other native-Swift builder, does not mention Android on its site, so it is not on this list.

Base44. “Your mobile app runs your published Base44 app inside a secure web view. This is a lightweight native wrapper around your web app that opens only your app’s URL.” Base44 generates the IPA and AAB on the Builder plan ($40 a month billed annually) or higher; “Full offline mode and HealthKit are not supported yet.”

GoodBarber. A managed no-code builder: “App native iOS e Android, pubblicate sull’App Store e su Google Play” (Italian site: native iOS and Android apps, published on the App Store and Google Play), with hosting included and, in its own words, “Non ti consegniamo codice” — it does not hand you code. Content plans from $30 a month billed yearly.

What you hold afterwards: for Base44, a React front-end via GitHub sync and a backend that stays on Base44; for GoodBarber, the published apps and your data, no project. Lovable is the exception that is not on this list: its docs say “Lovable does not generate React Native projects”, and its phone routes are a PWA or a Capacitor wrapper you set up yourself.

The groups answer differently, and the answer decides your testing budget.

In group 1 the two apps are the same screens, so behaviour matches by construction — and so does the look, which is the trade: an iPhone user and an Android user see the same design rather than their platform’s. In group 2 the behaviour is one codebase and the looks are two; parity is enforced by the build replaying recorded fixtures on both platforms and failing on a mismatch. In group 3 parity is your test plan: two codebases can drift on any commit, and nothing in the tool stops it. In group 4 there is one web app, so behaviour matches; what differs is what the wrapper exposes on each platform.

If your product is judged on whether it behaves correctly — payments, sync, anything with a rule — group 2 or group 1 keeps the two apps in step by mechanism; group 3 leaves it to your test plan.

Must the app use the platform’s own components and frameworks? Widgets, live activities, HealthKit, watch apps, App Intents, the platform’s navigation and controls. Yes → group 2 or 3 (native). No → group 1 or 4 is enough.

Who maintains the code in a year? A React Native or Flutter developer → group 1. An iOS and an Android developer, or you with an agent → group 2 or 3. Nobody, the vendor does → group 4.

Do you have a Mac? Group 2 needs one. Replit, Emergent and Base44 state that they do not. If the answer is no and the answer to the first question is yes, iOS or Android first helps you sequence rather than compromise.