Braintree/src/main/java/com/braintreepayments/api/DataCollector.java
public static void collectPayPalDeviceData(final BraintreeFragment fragment, final BraintreeResponseListener<String> listener) {
        final JSONObject deviceData = new JSONObject();

        try {
            String clientMetadataId = getPayPalClientMetadataId(fragment.getApplicationContext());
            if (!TextUtils.isEmpty(clientMetadataId)) {
                deviceData.put(CORRELATION_ID_KEY, clientMetadataId);
            }
        } catch (JSONException ignored) {}

        listener.onResponse(deviceData.toString());
    }
public static void collectPayPalDeviceData(final BraintreeFragment fragment, final BraintreeResponseListener<String> listener) {
        final JSONObject deviceData = new JSONObject();

        try {
            String clientMetadataId = getPayPalClientMetadataId(fragment.getApplicationContext());
            if (!TextUtils.isEmpty(clientMetadataId)) {
                deviceData.put(CORRELATION_ID_KEY, clientMetadataId);
            }
        } catch (JSONException ignored) {}

        listener.onResponse(deviceData.toString());
    }
Collect PayPal device information for fraud identification purposes.

@param fragment {@link BraintreeFragment}
@param listener listener to be called with the device data String to send to Braintree.