Apple has updated its iTunes U app for the iPad to version 3.5. It’s a free download and is compatible with iOS 9.3 or later.
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iTunes U provides tools for an instructor to bring a classroom together on the iPad. Users can build lessons with apps and your own materials, collect and grade assignments from students, start class discussions or talk with students one-on-one to answer questions and provide feedback.
Version 3.5 allows you to mark up photos with instructions or comments using built-in annotation tools. You can now send video messages and feedback in 1:1 chats between teachers and students and open audio or video files directly in other apps.