With the (experimental) MIDI Clock Sync Generator you can crate your own sample accurate timing signals and forward them to other devices and apps, independently of the hosts tempo. It also can be used as a diagnostic tool.
The Audio Unit requires a host application, which is able to handle MIDI messages, even supporting this kind of special MIDI realtime messages. It may be therefore not usable with any available AUv3 host, most likely due to the lack of support of MC. ^^
The complete manual is shipped with the distribution app.
The distribution app basically demonstrates a sender and a receiver of MIDI Clock pulses, driven by the sample accurate iOS audio engine. It has Core MIDI functionality built in.