# iOS Architecture ## Layer Model - UIKit/SwiftUI app layer. - Meeting orchestration layer (state machine + delegate fan-out). - SDK adapter layer (MobileRTC service wrappers). - Backend signature/token service. ## Reference Flow ```text iOS UI -> Meeting Coordinator -> Backend Sign Service -> Meeting SDK ^ | | | | v v v User intents Local state store Role/token policy SDK delegates/events ``` ## Why this split - Keeps security-critical logic server-side. - Stabilizes delegate/event ordering. - Makes upgrade drift easier to isolate.