Guideline 4.0: App Layout

Hi!

I'm new to developing and I tried to submit my app for review and was told that the app is not visually designed for an iPad. I made this app with the intent that it was going to be used on an iPhone because that's what the students in my classes mostly have. Can someone help with making this app iPad friendly? Whenever I tried to do it, it would change the entire format of the app, and I don't want to do that. Thank you in advance!

Guideline 4.0: App Layout
 
 
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