Turnitin have now released an update for the Feedback Studio iOS App which resolves this issue. Please make sure to sync all your grades and feedback before updating!
More Information: Feedback Studio for iOS Release Notes
Currently when using the Turnitin App on an Apple device, users might have difficulty accessing a paper’s information using the information button.
It appears that there is no information loading in the window, but this is a rendering issue not an app issue.
If you scroll up and down on the information box which opens, the information gradually appears.