I use Audiobus 2 App and the problem is that Eventide UltraTap doesn’t display in the Effect tab, neither the other ones as you can see from the attached screenshot.
The UltraTap version is that one of two days ago.
UltraTap should be compatible in the "Audio Units" tab of AudioBus, when you go to add an effect. Does it show up there?
Also make sure you have the latest version of UltraTap updated on your iDevice.