“AudioTools is our premier audio test and acoustical analysis app. AudioTools makes all of the Studio Six Digital audio and acoustics apps available in one package, adds more modules for line input audio analysis, and is also the app that works with iAudioInterface.”
Please be advised that iAudioInterface is currently sold out on the Studio Digital Six website. iAudioInterface 2 will be replacing it.
“AudioTools includes a base set of apps in the initial purchase price, and then has a number of optional modules that you can purchase from within AudioTools, if you decide that you want them. This mechanism, which Apple introduced in OS 3.0, is called “in-app purchasing”.”