Aux – Music app for your NAS

Aux is a music player for your Synology NAS.
The Aux app works with Audio Station running on your NAS to stream or download any audio file compatible with iOS, including lossless and high resolution audio formats — MP4 / AAC, MP3, Apple Lossless, FLAC, WAV, Dolby Digital, Dolby Digital Plus, and Dolby Atmos spatial audio.
Aux is a fast, ad-free, and feature-rich app that connects directly to your NAS. Since Aux uses no servers of its own, your username, password, and all your other data are exchanged securely and directly with your NAS. If you've chosen not to expose your NAS directly to the internet, Aux also works with Synology's own QuickConnect service to relay the connection through Synology's secure servers.
Server Management
• Secure, encrypted, and HTTPS-only network connections.
• Connect by QuickConnect ID, HTTPS URL, DDNS, or IP address.
• Secure, encrypted login with 2FA / OTP support.
• Secure Keychain storage with Touch ID, Face ID, or passcode protection to access your saved password.
• Multiple server / NAS support.
• Download mode for offline playback.
• Streaming mode for real-time playback.
• Dynamic, automatic reconnection when switching networks while using QuickConnect (LAN to WAN and vice versa).
• Download manager to pause, cancel, reorder, and restart downloads.
• Smart management of background and audio download sessions to keep downloads going in the background.
Folder Browsing
• Audio Station folder browsing.
• File Station folder browsing (to view artwork images, info files, or download files / formats not recognized by Audio Station).
• Pinned folder support for quick access to favorites.
• Search your NAS or downloaded files across artist, album, track title, or file / folder name — then navigate directly to a result or automatically through the folder hierarchy.
• Link sharing (DSM) and file export support (iOS share sheet).
• Queue downloads of entire folders and subfolders.
• View MP3 / MP4 / FLAC tags and audio metadata indexed by Audio Station.
• View album and file artwork, tap to view fullscreen.
• Build a playlist with replace, shuffle, insert, append.
• Choose to download or stream audio with a default setting and when adding items to your playlist.
Audio Player
• Plays any audio format supported by iOS, including Dolby Audio formats not supported by Audio Station.
• Gapless playback.
• Lossless and high resolution audio support (only limited by your DAC — no more forced transcoding to 16/48 WAV as with… another app).
• Seek & skip with Siri, lock screen, headphone remote, or in-app controls.
• Tap & hold to seek ahead / back instantly (no more waiting to seek).
• Seek across track boundaries to hear the end of that last song one more time.
• Artwork view for album / file artwork, tap to view fullscreen.
• Playlist view to manage the playlist queue.
• Metadata view for MP3 / MP4 / FLAC tags and audio metadata.
• AirPlay output controls with bitstreaming / buffering options.
• Shuffle / unshuffle, repeat track, repeat playlist.
• Saves playlist and playback position across app launches.
UI
• Optimized UI for one-handed use on the go, leveraging the lower third of the screen for important controls.
• Quick list controls — tap & hold to enter edit mode, two-finger drag to select, buttons to select all / none, pin, share, add to playlist, download.
• Haptic feedback for gestures and interactions.
• Many customization options —
• Keep-ahead x tracks for downloads/streams
• Choose between skip or seek controls
• Skip/seek by x seconds
• Pause audio on interruptions
• AirPlay bitstreaming (for surround sound) or 24-bit / 48kHz ALAC buffering
• Replace or append to the current playlist by default
• Written with the latest native Apple technologies from the ground up — Swift, SwiftUI, SwiftData, etc.
Aux is developed independently and is not affiliated with Synology Inc.
Terms of Use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula