Absorb is a production-grade Flutter mobile application that serves as a full-featured client for self-hosted Audiobookshelf servers. It streams and downloads audiobooks and podcasts, providing offline playback, sleep timer, bookmarking, chapter navigation, built-in equalizer, on-device speech-to-text transcription via whisper.cpp, and an ebook reader. The architecture is a cross-platform Flutter app with extensive native platform code (Kotlin for Android, Swift/ObjC for iOS) that deeply integrates with Android Auto, Apple CarPlay, Wear OS, Chromecast, and home-screen widgets. Audio playback is managed by a highly customized audio_service plugin with a native iOS audio engine (AbsorbAudioEngine) that handles cross-book transitions and equalizer effects. The transcription feature uses a forked whisper_ggml_plus package with a voxel-activity detection and MP3 slicer for frame-accurate clip extraction. The codebase demonstrates high craftsmanship in platform-level audio handling, but its reliance on multiple vendored plugins (audio_service, just_audio, flutter_carplay, whisper_ggml_plus, flutter_epub_viewer) creates maintenance overhead due to duplicated native code across platforms and occasional divergence from upstream versions.