I am trying to use my ipad primarily to take these practice questions and was wondering if anyone knew if the "highlight" feature is available on the iPad or only on the computer version. Thanks!

no highlighting on ipad app

Yes, you can highlight on the ipad.

The functionality of highlighting on the ipad is very rough still. You have to select the word that you want by pressing and holding over it (just like in all other text formats). Then you click the "highlight" button that pops up above the selected word. drag the bar over to select words or sentences. It takes a lot of extra time to do it this way, which is why I have a hard time with the iPad version of it.