LacertosusDeus' NowPlayingIcon Jailbreak Tweak Changes the Music App Icon and Playback Window
NowPlayingIcon works with manymultimedia applications, in particular Apple Music and Spotify. Tweak changes not only the application icon, but also the music playback window on the locked screen, in the application switcher and other places.
To use the NowPlayingIcon tweak, just install it. No additional settings. To disable the tweak, delete it.
NowPlayingIcon tweak is available for free in the Twickd repository. It supports “hacked” devices with iOS 13 (maybe it works with older versions of the OS).