Interview guides / ios

ARC and retain cycles: iOS Interview Question

ARC and retain cycles interview question with a clear example answer for iOS engineers. Practice with AceMobileInterview.

This is a common iOS interview topic: ARC and retain cycles.

Below is a concise answer you can adapt in a real interview, then go deeper in the full AceMobileInterview track.

1. 1.Explain Automatic Reference Counting (ARC). When do retain cycles happen, and how do you break them with weak and unowned references?

   ARC tracks strong references and frees objects at zero. Cycles usually appear in closures capturing self, or parent↔child object graphs. Use weak for optional back-references (delegates, closures that may outlive the object) and unowned when the reference is non-optional and guaranteed to outlive the capture. Always capture lists in escaping closures: `[weak self]`.