The Apparatus are accessed from the Passage Lookup display on the Translation/Commentary menu. Select Commentaries All and scroll down to the bottom of the list.
The VarApp apparatus displays the textual variants for the passage specified in the Bible Text field on the Passage Lookup screen. If you click on the yellow field/red dot i button just left of the Bible Text field a browser for VarApp apparatus a Apparatus browser displays.
VarApp apparatus Apparatus browser
SBLGNT apparatus
Note: The Apparatus are somewhat difficult to locate since you have to scroll all the way to the bottom of the commentary menu.
