要按设备而不是按用户的方式进行Google应用订阅，你可以使用Google Play Android开发者API来实现。以下是一个使用Java代码的示例：

import com.google.api.client.googleapis.auth.oauth2.GoogleCredential;
import com.google.api.client.googleapis.javanet.GoogleNetHttpTransport;
import com.google.api.client.http.HttpTransport;
import com.google.api.client.json.JsonFactory;
import com.google.api.client.json.jackson2.JacksonFactory;
import com.google.api.services.androidpublisher.AndroidPublisher;
import com.google.api.services.androidpublisher.AndroidPublisherScopes;
import com.google.api.services.androidpublisher.model.SubscriptionPurchase;

import java.io.File;
import java.io.IOException;
import java.security.GeneralSecurityException;
import java.util.Collections;

public class GooglePlaySubscriptionExample {

    private static final String APPLICATION_NAME = "Your Application Name";
    private static final String SERVICE_ACCOUNT_EMAIL = "your-service-account-email@your-project-id.iam.gserviceaccount.com";
    private static final String KEY_FILE_LOCATION = "/path/to/your/key.p12";
    private static final String PACKAGE_NAME = "com.example.yourapp";

    public static void main(String[] args) {
        try {
            HttpTransport httpTransport = GoogleNetHttpTransport.newTrustedTransport();
            JsonFactory jsonFactory = JacksonFactory.getDefaultInstance();

            // Load the service account credentials
            GoogleCredential credential = new GoogleCredential.Builder()
                    .setTransport(httpTransport)
                    .setJsonFactory(jsonFactory)
                    .setServiceAccountId(SERVICE_ACCOUNT_EMAIL)
                    .setServiceAccountPrivateKeyFromP12File(new File(KEY_FILE_LOCATION))
                    .setServiceAccountScopes(Collections.singleton(AndroidPublisherScopes.ANDROIDPUBLISHER))
                    .build();

            // Create the AndroidPublisher client
            AndroidPublisher androidPublisher = new AndroidPublisher.Builder(httpTransport, jsonFactory, credential)
                    .setApplicationName(APPLICATION_NAME)
                    .build();

            // Get the subscription purchase details for a specific device
            String purchaseToken = "your-purchase-token";
            SubscriptionPurchase purchase = androidPublisher.Purchases().subscriptions().get(PACKAGE_NAME, purchaseToken).execute();

            // Process the subscription purchase details
            String orderId = purchase.getOrderId();
            String purchaseState = purchase.getPurchaseState();
            String developerPayload = purchase.getDeveloperPayload();

            // Do something with the purchase details
            System.out.println("Order ID: " + orderId);
            System.out.println("Purchase State: " + purchaseState);
            System.out.println("Developer Payload: " + developerPayload);

        } catch (GeneralSecurityException | IOException e) {
            e.printStackTrace();
        }
    }
}

请注意，上述示例中的关键信息需要进行替换，以适应你自己的应用程序和服务帐户配置。你需要创建一个服务帐户并获得对应的私钥文件（P12格式）以供身份验证使用。此外，确保你的应用程序具有相应的Google Play Android开发者API权限。

此代码示例使用Google Play Android开发者API的AndroidPublisher客户端来获取订阅购买的详细信息，并且你可以进一步处理这些详细信息以满足你的需求。