diff --git a/demo/Android.bp b/demo/Android.bp
index 37fc676..749ca90 100644
--- a/demo/Android.bp
+++ b/demo/Android.bp
@@ -9,6 +9,7 @@
     static_libs: [
         "androidx-constraintlayout_constraintlayout",
         "androidx.appcompat_appcompat",
+        "com.android.microdroid.testservice-java",
         "com.google.android.material_material",
     ],
     libs: [
diff --git a/demo/java/com/android/microdroid/demo/MainActivity.java b/demo/java/com/android/microdroid/demo/MainActivity.java
index 6a46f73..ce21fdf 100644
--- a/demo/java/com/android/microdroid/demo/MainActivity.java
+++ b/demo/java/com/android/microdroid/demo/MainActivity.java
@@ -18,7 +18,9 @@
 
 import android.app.Application;
 import android.os.Bundle;
+import android.os.IBinder;
 import android.os.ParcelFileDescriptor;
+import android.os.RemoteException;
 import android.system.virtualmachine.VirtualMachine;
 import android.system.virtualmachine.VirtualMachineCallback;
 import android.system.virtualmachine.VirtualMachineConfig;
@@ -38,6 +40,8 @@
 import androidx.lifecycle.Observer;
 import androidx.lifecycle.ViewModelProvider;
 
+import com.android.microdroid.testservice.ITestService;
+
 import java.io.BufferedReader;
 import java.io.FileInputStream;
 import java.io.IOException;
@@ -45,6 +49,7 @@
 import java.io.InputStreamReader;
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
+import java.util.concurrent.Future;
 
 /**
  * This app is to demonstrate the use of APIs in the android.system.virtualmachine library.
@@ -141,7 +146,7 @@
         public void run(boolean debug) {
             // Create a VM and run it.
             // TODO(jiyong): remove the call to idsigPath
-            mExecutorService = Executors.newFixedThreadPool(2);
+            mExecutorService = Executors.newFixedThreadPool(3);
 
             VirtualMachineCallback callback =
                     new VirtualMachineCallback() {
@@ -177,9 +182,55 @@
 
                         @Override
                         public void onPayloadReady(VirtualMachine vm) {
-                            // This check doesn't 100% prevent race condition, but is fine for demo.
-                            if (!mService.isShutdown()) {
-                                mPayloadOutput.postValue("(Payload is ready)");
+                            // This check doesn't 100% prevent race condition or UI hang.
+                            // However, it's fine for demo.
+                            if (mService.isShutdown()) {
+                                return;
+                            }
+                            mPayloadOutput.postValue("(Payload is ready. Testing VM service...)");
+
+                            Future<IBinder> service;
+                            try {
+                                service = vm.connectToVsockServer(ITestService.SERVICE_PORT);
+                            } catch (VirtualMachineException e) {
+                                mPayloadOutput.postValue(
+                                        String.format(
+                                                "(Exception while connecting VM's binder"
+                                                        + " service: %s)",
+                                                e.getMessage()));
+                                return;
+                            }
+
+                            mService.execute(() -> testVMService(service));
+                        }
+
+                        private void testVMService(Future<IBinder> service) {
+                            IBinder binder;
+                            try {
+                                binder = service.get();
+                            } catch (Exception e) {
+                                if (!Thread.interrupted()) {
+                                    mPayloadOutput.postValue(
+                                            String.format(
+                                                    "(VM service connection failed: %s)",
+                                                    e.getMessage()));
+                                }
+                                return;
+                            }
+
+                            try {
+                                ITestService testService = ITestService.Stub.asInterface(binder);
+                                int ret = testService.addInteger(123, 456);
+                                mPayloadOutput.postValue(
+                                        String.format(
+                                                "(VM payload service: %d + %d = %d)",
+                                                123, 456, ret));
+                            } catch (RemoteException e) {
+                                mPayloadOutput.postValue(
+                                        String.format(
+                                                "(Exception while testing VM's binder service:"
+                                                        + " %s)",
+                                                e.getMessage()));
                             }
                         }
 
diff --git a/tests/aidl/Android.bp b/tests/aidl/Android.bp
new file mode 100644
index 0000000..893ec0b
--- /dev/null
+++ b/tests/aidl/Android.bp
@@ -0,0 +1,18 @@
+package {
+    default_applicable_licenses: ["Android-Apache-2.0"],
+}
+
+aidl_interface {
+    name: "com.android.microdroid.testservice",
+    srcs: ["com/android/microdroid/testservice/**/*.aidl"],
+    unstable: true,
+    backend: {
+        java: {
+            platform_apis: true,
+            gen_rpc: true,
+        },
+        cpp: {
+            enabled: true,
+        },
+    },
+}
diff --git a/tests/aidl/com/android/microdroid/testservice/ITestService.aidl b/tests/aidl/com/android/microdroid/testservice/ITestService.aidl
new file mode 100644
index 0000000..cdcb2bd
--- /dev/null
+++ b/tests/aidl/com/android/microdroid/testservice/ITestService.aidl
@@ -0,0 +1,24 @@
+/*
+ * Copyright 2021 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.android.microdroid.testservice;
+
+/** {@hide} */
+interface ITestService {
+    const int SERVICE_PORT = 5678;
+
+    /* add two integers. */
+    int addInteger(int a, int b);
+}
diff --git a/tests/testapk/Android.bp b/tests/testapk/Android.bp
index f545f8e..0b0810f 100644
--- a/tests/testapk/Android.bp
+++ b/tests/testapk/Android.bp
@@ -19,8 +19,11 @@
     srcs: ["src/native/testbinary.cpp"],
     shared_libs: [
         "android.system.keystore2-V1-ndk",
+        "android.system.virtualmachineservice-ndk",
+        "com.android.microdroid.testservice-ndk",
         "libbase",
         "libbinder_ndk",
+        "libbinder_rpc_unstable",
         "MicrodroidTestNativeLibSub",
     ],
 }
diff --git a/tests/testapk/src/native/testbinary.cpp b/tests/testapk/src/native/testbinary.cpp
index 1572021..2903a08 100644
--- a/tests/testapk/src/native/testbinary.cpp
+++ b/tests/testapk/src/native/testbinary.cpp
@@ -14,11 +14,21 @@
  * limitations under the License.
  */
 #include <aidl/android/system/keystore2/IKeystoreService.h>
+#include <aidl/android/system/virtualmachineservice/IVirtualMachineService.h>
+#include <aidl/com/android/microdroid/testservice/BnTestService.h>
 #include <android-base/result.h>
+#include <android-base/unique_fd.h>
 #include <android/binder_auto_utils.h>
 #include <android/binder_manager.h>
+#include <fcntl.h>
+#include <linux/vm_sockets.h>
+#include <stdint.h>
 #include <stdio.h>
+#include <sys/ioctl.h>
 #include <sys/system_properties.h>
+#include <unistd.h>
+
+#include <binder_rpc_unstable.hpp>
 
 using aidl::android::hardware::security::keymint::Algorithm;
 using aidl::android::hardware::security::keymint::Digest;
@@ -35,8 +45,12 @@
 using aidl::android::system::keystore2::KeyDescriptor;
 using aidl::android::system::keystore2::KeyMetadata;
 
+using aidl::android::system::virtualmachineservice::IVirtualMachineService;
+
+using android::base::ErrnoError;
 using android::base::Error;
 using android::base::Result;
+using android::base::unique_fd;
 
 extern void testlib_sub();
 
@@ -184,9 +198,63 @@
     return result;
 }
 
+Result<unsigned> get_local_cid() {
+    // TODO: remove this after VS can check the peer addresses of binder clients
+    unique_fd fd(open("/dev/vsock", O_RDONLY));
+    if (fd.get() == -1) {
+        return ErrnoError() << "failed to open /dev/vsock";
+    }
+
+    unsigned cid;
+    if (ioctl(fd.get(), IOCTL_VM_SOCKETS_GET_LOCAL_CID, &cid) == -1) {
+        return ErrnoError() << "failed to IOCTL_VM_SOCKETS_GET_LOCAL_CID";
+    }
+
+    return cid;
+}
+
+Result<void> start_test_service() {
+    class TestService : public aidl::com::android::microdroid::testservice::BnTestService {
+        ndk::ScopedAStatus addInteger(int32_t a, int32_t b, int32_t* out) override {
+            *out = a + b;
+            return ndk::ScopedAStatus::ok();
+        }
+    };
+    auto testService = ndk::SharedRefBase::make<TestService>();
+
+    auto callback = []([[maybe_unused]] void* param) {
+        // Tell microdroid_manager that we're ready.
+        // Failing to notify is not a fatal error; the payload can continue.
+        ndk::SpAIBinder binder(
+                RpcClient(VMADDR_CID_HOST, IVirtualMachineService::VM_BINDER_SERVICE_PORT));
+        auto virtualMachineService = IVirtualMachineService::fromBinder(binder);
+        if (virtualMachineService == nullptr) {
+            std::cerr << "failed to connect VirtualMachineService";
+            return;
+        }
+        if (auto res = get_local_cid(); !res.ok()) {
+            std::cerr << "failed to get local cid: " << res.error();
+        } else if (!virtualMachineService->notifyPayloadReady(res.value()).isOk()) {
+            std::cerr << "failed to notify payload ready to virtualizationservice";
+        }
+    };
+
+    if (!RunRpcServerCallback(testService->asBinder().get(), testService->SERVICE_PORT, callback,
+                              nullptr)) {
+        return Error() << "RPC Server failed to run";
+    }
+
+    return {};
+}
+
 } // Anonymous namespace
 
 extern "C" int android_native_main(int argc, char* argv[]) {
+    // disable buffering to communicate seamlessly
+    setvbuf(stdin, nullptr, _IONBF, 0);
+    setvbuf(stdout, nullptr, _IONBF, 0);
+    setvbuf(stderr, nullptr, _IONBF, 0);
+
     printf("Hello Microdroid ");
     for (int i = 0; i < argc; i++) {
         printf("%s", argv[i]);
@@ -201,5 +269,10 @@
     __system_property_set("debug.microdroid.app.run", "true");
     if (!report_test("keystore", test_keystore()).ok()) return 1;
 
-    return 0;
+    if (auto res = start_test_service(); res.ok()) {
+        return 0;
+    } else {
+        std::cerr << "starting service failed: " << res.error();
+        return 1;
+    }
 }