Suggested approach: Core Data is a huge and complex topic, but you should at least have tried it once. You might find it useful to talk about how
NSPersistentContainer made Core Data easier to use from iOS 10 onwards, or compare and contrast Core Data and CloudKit.
For a really great answer, talk about things that Core Data does well such as searching, sorting, and relationships, but also talk about places where Core Data struggles such as optionality and extensive stringly typed APIs.
Estimated difficulty: Easy
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