OS-39: Offline Music Player

Experience your music collection through a lens of clean design and technical precision. OS-39 is a premium Digital Audio Player (DAP) designed for those who value their local offline music library, offering a focused listening experience without subscriptions, ads, or distractions.
YOUR COLLECTION, YOUR WAY
OS-39 is built for your offline collection of music and allows you to play your high-quality audio files directly from the Files app using advanced in-place linking.
Whether it's FLAC, ALAC, or MP3, OS-39 handles your high-fidelity files with ease.
IMMERSIVE VISUALS
Get lost in the music with reactive visualizers. From the fluid "Aurora" backgrounds to the tactile "Ripple" fields, your screen becomes a functional extension of the soundscape.
PRO-GRADE AUDIO CONTROL
Tailor every track with a simple 5-band or professional 10-band ISO Equalizer.
Save custom EQ profiles for specific albums or playlists to ensure your gear always sounds its best.
SMART DISCOVERY
The on-device OS-39 Recommendation Engine learns your habits based on time, day, and season. Rediscover your library with "Forgotten Gems" and personalized daily suggestions that never leave your device. Your data stays private, offline, and secure. Want to know how the Engine works and learns? You can view it in the app, and enable or disable it as you wish.
KEY FEATURES:
• Gapless Playback & Customizable Crossfade (Pro)
• 10-Band Equalizer with Presets (Pro)
• Import our Music: Play directly from the Files app
• Beautiful Aesthetic Themes: Vocaloid, Sakura, Tokyo Tower, and more
• Interactive Widgets: Quick access to your favorites and recent plays
• Haptic Feedback: A tactile, mechanical feel to every interaction
• Privacy First: No tracking, no data collection, 100% offline
UPGRADE TO PRO
Unlock the full OS-39 experience with a simple one-time purchase. No subscriptions, forever.
• Advanced Playback: Gapless & Crossfade
• Full 10-Band Equalizer Access
• Exclusive Premium Themes
• Exclusive Visualizers
• Enhanced Library Intelligence
Elevate your listening experience. Welcome to OS-39.