Plays more than the built-in player ever will.
Common audio and video take the native playback path. Everything else (MKV, WebM, AVI, TS, APE, WMA, WavPack, AC3, DTS and many more containers and codecs) can go through a VideoLAN-based universal decoder path. DSF and uncompressed DFF DSD play through a decode-to-PCM path, stated as exactly that. Format and feature availability varies by file, device and decoder; the app says so instead of promising "everything".
The listening tools, all local.
A 31-band EQ, stereo crossfeed, gapless playback, crossfade, A/B repeat, bookmarks, sleep fade, ReplayGain with a true-peak safety estimate, a real waveform scrubber, and word-timed LRC lyrics. Player Go Full adds headphone correction on top.
Made for your Apple devices.
Lock Screen and Control Center playback, AirPlay output, the iPad sidebar, CarPlay with library, Up Next and full lyrics, a Home Screen widget with recent playback, Siri and Shortcuts, and an Apple Watch app that both remote-controls the phone and caches audio for offline listening.
Your listening stays on the device.
Listening history and stats live on your device, with CSV export and a full delete-history reset. Nothing is uploaded. Last.fm scrobbling is a separate, explicit opt-in. Credentials for network sources are used for the session only, unless you explicitly choose to remember them. Then they go into the device-only Keychain, never into any file that leaves any device.