default-communication-app-workflow

Default Communication App Workflow

Purpose

Choose the documented default-app role before building routing, UI, account, or transport logic. A default messaging app, default calling app, default dialer, and default carrier messaging app are separate products with different system contracts.

iOS And iPadOS Roles

1. Default instant messaging app: requires the Default Messaging App entitlement and im: URL handling. It receives a recipient address, not arbitrary message body content; provide sms: fallback only when the app cannot handle the recipient.
2. Default calling app: requires real VoIP capability, the Default Calling App entitlement, voip background mode, and CallKit or LiveCommunicationKit. Handle tel: routing and offer an explicit system fallback when VoIP cannot complete.
3. Default dialer: uses LiveCommunicationKit for cellular conversation initiation and has a separate Default Dialer App entitlement. Treat EU account/device requirements as release gates, not implementation details.
4. Default carrier messaging app: uses TelephonyMessagingKit for SMS, MMS, and RCS. Keep its entitlement, carrier behavior, user data, and EU availability separate from internet messaging.

macOS Boundary

Do not claim a corresponding documented macOS default messaging or calling-app role without current Apple evidence. When building for macOS, implement an app-owned messaging/calling client, account setup, local notifications, contacts/share integrations where available, and companion continuity behavior. That client must not imply access to Apple Messages, Phone, carrier SMS/MMS/RCS, or system call routing.

Validation And Release Gates

Validate default-role selection, URL routing, unavailable-recipient and transport fallback, entitlement/provisioning state, privacy disclosures, physical-device behavior, regional availability, and App Review evidence. Keep each role's capability inventory in the app project; do not silently enable an entitlement because another communication role needs it.

References

• Preparing your app to be the default messaging app
• Preparing your app to be the default calling app
• Preparing your app to be the default dialer app
• Creating a carrier messaging app