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# AVExternalStorageDeviceDiscoverySession

Informs your app when the external storage devices connect to and disconnect from the system.

```
class AVExternalStorageDeviceDiscoverySession
```

## Topics

### Checking for session support on a device

[`isSupported`](/documentation/AVFoundation/AVExternalStorageDeviceDiscoverySession/isSupported)

A Boolean value that indicates whether the system supports external storage devices.

### Retrieving the shared device discovery session instance

[`shared`](/documentation/AVFoundation/AVExternalStorageDeviceDiscoverySession/shared)

The system’s singleton device discovery session instance.

### Monitoring for storage device updates

[`externalStorageDevices`](/documentation/AVFoundation/AVExternalStorageDeviceDiscoverySession/externalStorageDevices)

An array of external storage devices the session updates as individual devices connect or disconnect from the system.


---

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