Zello Emergency & Dispatch

This skill covers the highest-stakes feature in the Zello integration — emergency mode and its integration with the existing Code21 dispatch system.

Zello Emergency Mode

When activated, emergency mode:

• Opens a priority audio channel to dispatch (overrides all mute settings)
• Sends the officer's location automatically
• Triggers a prominent alert on the dispatch console
• Remains active until explicitly deactivated

Zello.startEmergency();  // Activate
Zello.stopEmergency();   // Deactivate

Code21 Dual-Trigger Pattern

Zello emergency complements Code21 — it does not replace it. When an officer triggers emergency, fire both systems:

Scenario	Code21	Zello Emergency
Dispatch sends job to officer	✅ Push notification	—
Officer acknowledges dispatch	✅ API call	—
Officer needs immediate help	—	✅ Live voice + location
Officer sends status update	✅ API status change	✅ PTT voice

Emergency Hook

// src/features/zello/hooks/useZelloEmergency.ts
import Zello from '@zelloptt/react-native-zello-sdk';
import api from '@/shared/infra/api';

export function useZelloEmergency() {
  const startEmergency = async () => {
    // 1. Activate Zello emergency (live voice + location)
    Zello.startEmergency();

    // 2. Notify MAPS API (creates Code21 record, alerts supervisors)
    try {
      await api.post('/code21/emergency', {
        type: 'OFFICER_EMERGENCY',
        source: 'zello',
      });
    } catch {
      // Zello emergency is already active — API failure is non-blocking
      console.error('[EMERGENCY] Failed to notify MAPS API');
    }
  };

  const stopEmergency = () => {
    Zello.stopEmergency();
  };

  return { startEmergency, stopEmergency };
}

The Zello emergency takes priority — even if the MAPS API call fails, the officer has live voice and location streaming to dispatch.

Receiving Emergency Events

For dispatch/supervisor app:

Zello.Listener.on('onEmergencyStarted', (event) => {
  // event.contact — officer in emergency
  // Highlight on patrol map, sound alarm, bring to front
});

Zello.Listener.on('onEmergencyStopped', (event) => {
  // Clear emergency state
});

Emergency Button UX

Officer safety requirements:

• Place in a persistent, accessible location — not buried in a menu
• Use a long-press gesture (3-second hold) to prevent accidental activation
• Provide strong visual + haptic + audio feedback on activation
• Make deactivation equally clear but not accidentally triggerable

Dispatch Calls

For non-emergency priority communications:

await Zello.sendDispatchCall(dispatchChannel);

This requests attention from dispatch without triggering full emergency mode.

Detailed Documentation

See docs/dev/zello/10-emergency-dispatch.md for the full emergency and dispatch guide.