EQK utilises an on device engine that is constantly being refined to not only give accurate sounds but sounds that adapts to the users tastes/ears, listening habits and their headphones strengths and weaknesses. The engine utilises a structure very similar to weights to make these decisions and the weights are updated by apple intelligence in the background for user taste and preferences.
The star feature of the app however is the dynamic real time EQ, that tries to (and does so well by the positive feedback received till date) EQ songs on the go, applying varying adjustments each second of the song, and also saves a fully EQ'd songs profile to memory, so on your next run the real-time EQ experience is optimised to the engine's potential.

The app also supports a static EQ for those that prefer a linear and stable EQ experience along with over 2,900 Headphone correction profiles from AutoEQ.

The app also comes bundled with a built in hi-res player with lyrics support, support for most major entertainment apps including- Apple Music, Spotify, Netflix, Amazon prime, and any Safari tab you save as an app and can play audio.