The Tool Desk
Outbyte Driver Updater FREEScan for outdated or missing drivers - takes under a minuteDriver Scan →Outbyte PC Repair FREEClear out junk files and repair common Windows errorsFree Scan →For a new Android app, start with Kotlin: Google describes Android development as Kotlin-first and recommends Kotlin for new projects. Java is still supported, and both languages can live in the same app, so existing Java code or team expertise does not require a rewrite.
Which language should you choose for Android?
Choose Kotlin for a new project unless a concrete constraint—such as an established Java codebase or a team’s existing expertise—makes Java or a mixed-language approach more practical. Android’s Kotlin-first direction means its newer tools, libraries, samples, documentation, and training are designed with Kotlin users in mind; it does not mean Java has been removed.
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Google’s Android Developers guidance explains its Kotlin-first approach at Android development with Kotlin. The recommendation is a useful default, not a requirement that every Android app use Kotlin.
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One free scan finds every outdated or missing driver and matches the right update for your exact hardware.Free scan · exact hardware matchHow Kotlin and Java compare on Android
| Consideration | Kotlin | Java |
|---|---|---|
| Starting a new Android app | Google’s recommended starting language; newer Android resources are Kotlin-first. | Supported, though newer training, samples, and some resources receive best-effort support. |
| Android Studio and SDK | Supported, including Kotlin source files and conversion tooling. | Supported and suitable for existing projects; Java files can coexist with Kotlin files. |
| Using existing code | Can call Java APIs and libraries, making incremental adoption practical. | Can call Kotlin code, though some Kotlin-specific features need interoperation considerations. |
| Kotlin-specific Android ecosystem | Android offers Kotlin extensions (KTX), coroutines, Jetpack Compose, and Kotlin-focused learning resources. | The Android platform SDK remains supported, but some Kotlin-specific APIs and tools do not have Java equivalents. |
These differences describe ecosystem support, not a guarantee that one language makes every app faster, more reliable, or easier to maintain. Project needs and the code already in place still matter.
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Can one Android app use both Kotlin and Java?
Yes. Kotlin and Java interoperate, and a project can contain source files in both languages. Kotlin code can use Java classes, APIs, and libraries, so a team can keep working Java code while adding new Kotlin code where it makes sense. This avoids treating adoption as an all-or-nothing migration.
Android Studio includes Java-to-Kotlin conversion tooling. Treat conversion as a starting point rather than a guarantee of finished code: review the result and run the project’s tests, as Android’s FAQ advises. See Android’s Kotlin FAQ for interoperation and conversion details.
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What Kotlin adds to Android development
- Kotlin extensions (KTX): Kotlin-specific APIs that provide more idiomatic ways to work with parts of the Android and Jetpack libraries.
- Coroutines: Kotlin’s concurrency features, supported in Android’s Kotlin ecosystem.
- Jetpack Compose: Android’s modern UI toolkit is part of the Kotlin-focused development ecosystem.
- Kotlin-oriented resources: Google’s newer Android documentation, samples, and training emphasize Kotlin.
These features can be reasons to choose Kotlin for new work, but they are options rather than prerequisites for building an Android app. Java remains a supported choice for projects whose requirements and existing code favor it.
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1Scan for outdated or missing drivers - takes under a minute2Clear out junk files and repair common Windows errors3Fix the driver behind crashes, sound loss and screen glitchesDo not confuse the Java version with Android’s runtime APIs
Android build settings involve several separate concepts: the JDK used to run Android Studio or Gradle, the Java toolchain used to compile source, the Java language compatibility level, and the APIs available on a device’s Android version. A project’s Java compatibility setting does not mean every JDK API is available on every Android device. Android provides a subset of JDK APIs; availability depends on Android version, and desugaring can make some newer APIs usable on earlier versions.
For a specific project, check its Android Gradle Plugin, Kotlin plugin, compile SDK, minimum SDK, toolchain, and desugaring requirements together. Android’s JDK and Java versions documentation recommends explicitly specifying the Java toolchain to make builds more consistent across machines.
Independent reader supportYour contribution helps us test, update, and keep practical guides available for everyone.Choose a learning path that fits your starting point
If you are new to programming
Start with Google’s Android Basics in Kotlin. The course is intended for learners with no prior programming experience, uses Android Studio, and teaches app-building fundamentals with Kotlin.
If you already know Java
Keep your Java knowledge useful: learn Kotlin syntax and nullability, then introduce Kotlin alongside Java in a project. Interoperability lets you adopt it incrementally rather than translating the entire codebase first. If you use Android Studio’s conversion tool, review converted code and run tests.
If you want a book
Google’s official resource list includes a book resource titled “Android development with Kotlin.” The listing establishes that Google includes it as a learning resource, not that a particular edition is currently available from a retailer. Check the edition and availability before buying.
Google’s Android learning resources are collected at Books on Android development.
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