Skip (Swift on Android) vs Kotlin Multiplatform Comparison

// Skip: Setup and new project on a machine with Xcode + Android Studio installed
// Source: https://skip.dev/docs/gettingstarted/ + https://skip.dev/docs/skip-cli/

// 1) Install the Skip toolchain (Homebrew)
brew install skip

// 2) Verify the environment (Xcode, Android Studio, Java, Gradle versions)
skip checkup

// 3) Create a new Skip App project (Fuse mode, iOS+Android).
// `skip create` is fully interactive and takes no flags; the non-interactive equivalent is `skip init`:
skip init --native-app --appid=com.example.HelloSkip hello-skip HelloSkip

// 4) If you want to add Android to an existing iOS app via the Library model:
// extract the shared logic into a separate native library module
skip init --native-model shared-feature SharedFeature

// You write the resulting SwiftUI view just like an ordinary iOS SwiftUI view:
import SwiftUI

struct ContentView: View {
    @State private var count = 0

    var body: some View {
        VStack(spacing: 16) {
            Text("Shipping to Android with Skip")
                .font(.title2)
            Text("Count: \(count)")
            Button("Increment") {
                count += 1
            }
            .buttonStyle(.borderedProminent)
        }
        .padding()
    }
}

// 5) Build and run on the Android side (via Gradle, where under the hood
// the SwiftUI view tree is converted into Jetpack Compose calls).
// Prerequisite: start the emulator yourself — `skip app launch` doesn't start it for you.
cd hello-skip
skip android emulator launch
skip app launch --android

// Kotlin Multiplatform: shared logic + expect/actual
// Source: https://kotlinlang.org/docs/multiplatform/get-started.html

// commonMain/kotlin/Counter.kt — logic shared across all platforms
class Counter {
    private var value: Int = 0
    fun increment(): Int { value += 1; return value }
    fun current(): Int = value
}

// commonMain/kotlin/Platform.kt
expect fun platformName(): String

// androidMain/kotlin/Platform.android.kt
actual fun platformName(): String = "Android ${android.os.Build.VERSION.SDK_INT}"

// iosMain/kotlin/Platform.ios.kt
import platform.UIKit.UIDevice
actual fun platformName(): String =
    UIDevice.currentDevice.systemName() + " " + UIDevice.currentDevice.systemVersion

// On Android, the Compose UI uses the shared Counter
@Composable
fun CounterScreen(counter: Counter) {
    var count by remember { mutableStateOf(counter.current()) }
    Column(modifier = Modifier.padding(16.dp)) {
        Text("Shared logic with Kotlin Multiplatform")
        Text("Count: $count")
        Button(onClick = { count = counter.increment() }) { Text("Increment") }
    }
}

// build.gradle.kts (module: shared)
kotlin {
    androidTarget()
    listOf(iosX64(), iosArm64(), iosSimulatorArm64()).forEach {
        it.binaries.framework { baseName = "Shared" }
    }
    sourceSets {
        commonMain.dependencies {
            implementation("org.jetbrains.kotlinx:kotlinx-coroutines-core:1.9.0")
        }
    }
}