要实现安卓版的SendGrid，可以使用SendGrid提供的Java库来发送电子邮件。下面是一个使用SendGrid库的示例代码：

首先，将SendGrid库添加到你的Android项目中。在你的app级别的build.gradle文件中添加以下依赖项：

dependencies {
    implementation 'com.sendgrid:sendgrid-java:4.6.3'
}

然后，可以使用以下代码示例来发送电子邮件：

import com.sendgrid.*;

import java.io.IOException;

public class SendEmailTask extends AsyncTask {

    private static final String SENDGRID_API_KEY = "YOUR_SENDGRID_API_KEY";
    private static final String EMAIL_SENDER = "sender@example.com";
    private static final String EMAIL_RECIPIENT = "recipient@example.com";
    private static final String EMAIL_SUBJECT = "Hello from SendGrid";
    private static final String EMAIL_BODY = "This is the email body.";

    @Override
    protected Void doInBackground(Void... params) {
        Email from = new Email(EMAIL_SENDER);
        Email to = new Email(EMAIL_RECIPIENT);
        Content content = new Content("text/plain", EMAIL_BODY);
        Mail mail = new Mail(from, EMAIL_SUBJECT, to, content);

        SendGrid sg = new SendGrid(SENDGRID_API_KEY);
        Request request = new Request();

        try {
            request.setMethod(Method.POST);
            request.setEndpoint("mail/send");
            request.setBody(mail.build());
            Response response = sg.api(request);
            System.out.println(response.getStatusCode());
            System.out.println(response.getBody());
            System.out.println(response.getHeaders());
        } catch (IOException ex) {
            ex.printStackTrace();
        }

        return null;
    }
}

请确保将YOUR_SENDGRID_API_KEY替换为你的SendGrid API密钥。

在你的代码中调用SendEmailTask的execute()方法来发送电子邮件：

new SendEmailTask().execute();

这将在后台线程中发送电子邮件。请注意，发送电子邮件的API调用应该在后台线程中执行，以避免阻塞主线程。

使用上述代码示例，你可以在安卓应用中实现SendGrid的功能，并发送电子邮件。