Audio Damage has shared FuzzPlus 3, a direct 1:1 port of their free desktop plugin of the same name, as a free download for iOS
FuzzPlus 3 is an AUv3 or standalone audio effect that consists of a resonant lowpass filter (modeled on the MS20 LPF) and a distortion engine (modeled on the Distortion+ pedal) with a feedback loop.
AD says that FuzzPlus 3 ‘can do everything from simple filtering and warmth to full metal audio destruction’.
It’s a free download from the App Store.
standalone does not mean audiobus.
Who cares about Audiobus when you have AU..?