The appType property calls the viewerType property from the Acrobat JavaScript object model and returns the corresponding value for the client application in which the form exists. For example, in the context of a PDF form viewed in Adobe Reader, this property returns Reader.For more information on the viewerType property, and the values it returns, see the JavaScript for Acrobat API Reference at http://www.adobe.com/go/learn_lc_AcrobatDeveloper.