> **Key takeaway:**  ☞   The renaming of "Ledger Live" to "Ledger Wallet" and\
>      "wallet" (in the hardware sense) to "signer" is still in progress.\
>      This page may contain legacy references that will be updated.

# Using the Device Module in Wallet API Core Client

The Device Module provides methods for handling the physical device, including opening low-level transport and selecting a device in the connected wallet.

## Device Module Overview

Access the Device module via `walletApiClient.device`.

### Methods:

#### 1. Open Low-Level Transport

Open low-level transport in the connected wallet.

```javascript
walletApiClient.device.transport(params: DeviceTransport["params"]): Promise<HWTransport>
```

**Parameters**:

- `params`: An object containing the parameters for the transport.

**Returns**: A promise that resolves with an instance of Transport compatible with `@ledgerhq/hw-transport`.

[**Required permission**:](https://developers.ledger.com/docs/ledger-live/discover/guides/wallet-api/appendix/manifest#permissions)
`device.transport`

##### Example:

```javascript
async function openTransport(walletApiClient, params) {
  try {
    const transport = await walletApiClient.device.transport(params);
    console.log("Transport opened:", transport);
  } catch (error) {
    console.error("Error opening transport:", error);
  }
}
```

#### 2. Open Device

Open a device in the connected wallet.

```javascript
walletApiClient.device.open(params: DeviceOpen["params"]): Promise<HWTransport>
```

**Parameters**:

- `params`: An object containing the parameters to open the device.

**Returns**: A promise that resolves with an instance of Transport compatible with `@ledgerhq/hw-transport`.

[**Required permission**:](https://developers.ledger.com/docs/ledger-live/discover/guides/wallet-api/appendix/manifest#permissions)
`device.open`

##### Example:

```javascript
async function openDevice(walletApiClient, params) {
  try {
    const device = await walletApiClient.device.open(params);
    console.log("Device opened:", device);
  } catch (error) {
    console.error("Error opening device:", error);
  }
}
```

#### 3. Select Device

Select a device in the connected wallet.

```javascript
walletApiClient.device.select(params: DeviceSelect["params"]): Promise<DeviceSelect["result"]>
```

**Parameters**:

- `params`: An object containing the parameters to select and check the device.

**Returns**: A promise that resolves with a `deviceId` which can be used with the `device.open` method.

[**Required permission**:](https://developers.ledger.com/docs/ledger-live/discover/guides/wallet-api/appendix/manifest#permissions)
`device.select`

##### Example:

```javascript
async function selectDevice(walletApiClient, params) {
  try {
    const deviceId = await walletApiClient.device.select(params);
    console.log("Device selected, ID:", deviceId);
  } catch (error) {
    console.error("Error selecting device:", error);
  }
}
```

## Handling Errors

Make sure to handle errors gracefully and provide appropriate feedback to the user. Additionally, always remember to disconnect the `WindowMessageTransport` when you're done interacting with the  API to free up resources.