Codex vs Claude Code: Who Builds the Better iOS App?

I gave Claude Code and Codex the same prompt — build a native iOS health app with HealthKit and Swift Charts — and scored both on a four-point rubric: agent autonomy, app quality, native iOS fluency, and code quality. One of them is writing 2026 SwiftUI. The other one isn't. Chapters 0:00 Intro 0:27 The four-category rubric 0:37 Two Xcode projects, two terminals 1:02 The prompt 2:21 Both agents go to work 2:32 21 minutes vs 17 minutes 2:49 First look at Claude's app 3:11 First look at Codex's app 3:29 Round 1: Agent autonomy 3:51 Round 2: Final app quality 5:23 Round 3: Native iOS fluency 6:47 Round 4: Code quality 8:24 The verdict 9:12 Thanks for watching