What's better than something that still calls native APIs and compiles like native code for literally every platform out there? I love Kotlin. I also love Compose multiplatform, which provided the final missing piece of the whole thing, UI shared code.
That's why you'll find me writing everything for Kotlin and in Kotlin. I believe this will be the mainstream framework to go with when it comes to multiplatform app development. You'll find some nice libraries updated regularly to be up to speed with Kotlin's evolution, including the latest Koltin Toolchain (KTC, previously Amper) build system that replaces Gradle and rids you of the extra Gradle daemon burden :p
 Synkplay   Watch videos in sync with friends on Android and iOS. Anyone on a computer can join the same room with Syncplay. |
 KitePDF   Read, create, edit, and display PDFs, and open EPUB books. It is pure Kotlin, so the same code runs on Android, iOS, desktop, and the web. |
  KitePlayer + KiteFFmpeg   KiteFFmpeg adds FFmpeg to your project as one Gradle dependency, with no NDK and nothing to install. Use it to convert, trim, and transcode video and audio. KitePlayer is a media player built on KiteFFmpeg. Its core is 100% Kotlin, so it plays the same on every platform. It supports subtitles, live streams, and hardware decoding. |
 KiteConfig   Set your app name, icon, version, and IDs once, in one Gradle block. Android, iOS, and desktop all read from it, so they never drift apart. |
| ImageKodec | ArchiveKodec | AudioKodec |
|---|
| Library | Purpose |
|---|---|
| KiteJS | Run JavaScript from shared code, with Rhino or QuickJS behind one API. |
| KiteCore | The small helpers every project rewrites, like String.format() and Dispatchers.IO in commonMain. |
| Kite3D | 3D math: vectors, matrices, quaternions, and bounding volumes, with the same API as three.js. |
| libmpvKt | The mpv player engine for Android, prebuilt, with a typed Kotlin API. |
| Library | Purpose |
|---|---|
| KiteQR | Scan and create QR codes and barcodes. |
| KiteSynth | A synthesizer: it reads a SoundFont, takes MIDI notes, and turns them into sound. |
| KiteRT | Real-time audio output. Your code makes the samples, and KiteRT sends them to the speakers. |
| KiteMIDI | Read and write MIDI files, and talk to real instruments over USB and Bluetooth. |
| KiteTorrent | Download and seed torrents from shared code: magnet links, encryption, peer discovery. |
