The app compiled clean at 18.0 with no code change; 26.5 was the new-project default. Both packages accept iOS 16.
Verified on a downloaded iOS 18.6 runtime (iPhone 16) and on 26.5: unit suite green on both; all 14 live smoke tests green on both. Two things surfaced only on 18: tests that built their own decoder with .iso8601 failed on fractional seconds, so they now use GitbayClient.decoder(); and list section headers render uppercased, so the suite matches them ignoring case. The suite also signs in at setup when a device starts on the token screen.