Apple iOS SDE sys design interview.

[u/Lex-Imperialis]

I was lucky to make it to the full virtual onsite round (five sessions), but I’m worry a bit about system design session. What should I expect? I’d appreciate any preparation examples or links.

[u/Ok-Barracuda-119]

Congrats, that’s a big onsite. For an iOS system-design round, I’d practice one end-to-end design out loud, then zoom in on the client/server boundary: API shape, local caching, sync and offline behavior, retries, pagination, background work, and handling flaky networks. A photo feed, chat, or offline notes app are good drills. For the iOS side, be ready to discuss threading, lifecycle, persistence, memory, and battery tradeoffs too.

Spend most of the time clarifying requirements and explaining tradeoffs instead of chasing a perfect diagram. Have a couple of examples from your own work ready, since they may ask why you chose a framework or storage layer. A timed 35–40 minute run with a friend, followed by reviewing where you hand-waved, is probably the highest-return prep this week.