What is simpmusic?

SimpMusic is a free, open-source music player for Android and desktop that uses YouTube Music as its source of songs and playlists. It lets you play music from YouTube and YouTube Music without ads, without needing a paid subscription for most features, and with the audio playing in the background while you use other apps. It is available through F-Droid and IzzyOnDroid, which are app stores for free and open-source Android software. The app pulls music data from YouTube Music using unofficial methods, not an official API, which is a common approach for free YouTube clients but also means playback errors can occur when YouTube changes things on their end. The README acknowledges this openly and describes the app as still in beta. Feature-wise, it covers most things you would expect from a dedicated music app: home feed, charts, moods and genre browsing, search, custom playlists synced with your YouTube Music account, synced lyrics from multiple sources, caching for offline listening, a sleep timer, crossfade between tracks, and Android Auto support. Some features borrow ideas from other services: Spotify Canvas support (animated video backgrounds), SponsorBlock integration to skip sponsored segments inside music videos, and Return YouTube Dislike to show vote counts. AI song suggestions and AI lyrics translation are listed as beta features and require an OpenAI or Gemini API key you supply yourself. There are two versions: a FOSS build that collects no data at all, and a Full build that uses Sentry crash reporting to help the developer fix bugs. The README explains the difference clearly and lets users choose. The project is written in Kotlin and uses Compose Multiplatform, which is the technology that allows the same codebase to run on both Android and desktop. It credits several other open-source projects for ideas and code related to YouTube data extraction and streaming.