diff --git a/nearby/apex/Android.bp b/nearby/apex/Android.bp
index 540be44..b277ac4 100644
--- a/nearby/apex/Android.bp
+++ b/nearby/apex/Android.bp
@@ -40,6 +40,7 @@
     java_libs: [
         "service-nearby",
     ],
+    apps: ["HalfSheetUX"],
 }
 
 filegroup {
diff --git a/nearby/framework/Android.bp b/nearby/framework/Android.bp
index ba97112..1f1dac5 100644
--- a/nearby/framework/Android.bp
+++ b/nearby/framework/Android.bp
@@ -65,6 +65,7 @@
     installable: false,
     visibility: [
         "//packages/modules/Nearby/service",
+        "//packages/modules/Nearby/halfsheet",
         "//packages/modules/Nearby/tests",
     ],
 }
diff --git a/nearby/framework/java/android/nearby/IFastPairHalfSheetCallback.aidl b/nearby/framework/java/android/nearby/IFastPairHalfSheetCallback.aidl
new file mode 100644
index 0000000..43d31d1
--- /dev/null
+++ b/nearby/framework/java/android/nearby/IFastPairHalfSheetCallback.aidl
@@ -0,0 +1,24 @@
+// Copyright (C) 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 android.nearby;
+
+/**
+  * Provides callback interface for halfsheet to send FastPair call back.
+  *
+  * {@hide}
+  */
+interface IFastPairHalfSheetCallback {
+     void onHalfSheetConnectionConfirm();
+ }
\ No newline at end of file
diff --git a/nearby/halfsheet/Android.bp b/nearby/halfsheet/Android.bp
new file mode 100644
index 0000000..a1a90fb
--- /dev/null
+++ b/nearby/halfsheet/Android.bp
@@ -0,0 +1,51 @@
+// Copyright (C) 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 {
+    default_applicable_licenses: ["Android-Apache-2.0"],
+}
+
+java_defaults {
+    name: "HalfSheetDefaults",
+    srcs: ["src/**/*.java"],
+    sdk_version: "module_current",
+    min_sdk_version: "current",
+    target_sdk_version: "current",
+    manifest: "AndroidManifest.xml",
+    plugins: ["java_api_finder"],
+    jarjar_rules: ":nearby-jarjar-rules",
+    libs: [
+        "framework-nearby-pre-jarjar",
+        "nearby-service-string",
+      ],
+    static_libs: [
+        "androidx.annotation_annotation"
+    ],
+    lint: { strict_updatability_linting: true }
+}
+
+android_app {
+    name: "HalfSheetUX",
+    defaults: ["HalfSheetDefaults"],
+    resource_dirs: ["res"],
+    certificate: ":com.android.nearby.halfsheetcertificate",
+    updatable: true,
+    apex_available: ["com.android.nearby",],
+}
+
+android_app_certificate {
+    name: "com.android.nearby.halfsheetcertificate",
+    certificate: "apk-certs/com.android.nearby.halfsheet"
+}
+
diff --git a/nearby/halfsheet/AndroidManifest.xml b/nearby/halfsheet/AndroidManifest.xml
new file mode 100644
index 0000000..3e8b39b
--- /dev/null
+++ b/nearby/halfsheet/AndroidManifest.xml
@@ -0,0 +1,31 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+  ~ Copyright (C) 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.
+  -->
+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools"
+    package="com.android.nearby.halfsheet">
+    <application android:label="@string/app_name">
+        <activity
+            android:name="com.android.nearby.halfsheet.HalfSheetActivity"
+            android:exported="true">
+            <intent-filter>
+                <action android:name="android.nearby.SHOW_HALFSHEET"/>
+                <category android:name="android.intent.category.DEFAULT"/>
+            </intent-filter>
+        </activity>
+    </application>
+
+</manifest>
\ No newline at end of file
diff --git a/nearby/halfsheet/apk-certs/com.android.nearby.halfsheet.pk8 b/nearby/halfsheet/apk-certs/com.android.nearby.halfsheet.pk8
new file mode 100644
index 0000000..187d51e
--- /dev/null
+++ b/nearby/halfsheet/apk-certs/com.android.nearby.halfsheet.pk8
Binary files differ
diff --git a/nearby/halfsheet/apk-certs/com.android.nearby.halfsheet.x509.pem b/nearby/halfsheet/apk-certs/com.android.nearby.halfsheet.x509.pem
new file mode 100644
index 0000000..440c524
--- /dev/null
+++ b/nearby/halfsheet/apk-certs/com.android.nearby.halfsheet.x509.pem
@@ -0,0 +1,34 @@
+-----BEGIN CERTIFICATE-----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+bs97HJl9PgMCp7hP+dYDxEtNTAESg5IpJ1i7uINgPNl8d0tvJ9rOEdy0IcdeGwt/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+-----END CERTIFICATE-----
diff --git a/nearby/halfsheet/apk-certs/key.pem b/nearby/halfsheet/apk-certs/key.pem
new file mode 100644
index 0000000..e9f4288
--- /dev/null
+++ b/nearby/halfsheet/apk-certs/key.pem
@@ -0,0 +1,52 @@
+-----BEGIN PRIVATE KEY-----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+YCLC4VtJ4lE3wqthYjaz8pDiU+1PTQIDAQABAoICAQCt4R5CM+8enlka1IIbvann
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+xBKkc/nLSAiwtbjSTI7/qf8K0h752aTUOctpWWEnhZon00ywf4Ic3TbBatF/n/W/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+-----END PRIVATE KEY-----
diff --git a/nearby/halfsheet/res/layout/activity_half_sheet.xml b/nearby/halfsheet/res/layout/activity_half_sheet.xml
new file mode 100644
index 0000000..4915d4b
--- /dev/null
+++ b/nearby/halfsheet/res/layout/activity_half_sheet.xml
@@ -0,0 +1,20 @@
+<?xml version="1.0" encoding="utf-8" ?>
+<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    xmlns:tools="http://schemas.android.com/tools"
+    xmlns:app="http://schemas.android.com/apk/res-auto">
+
+    <LinearLayout
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        android:orientation="vertical" >
+
+        <TextView
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:text="abc half sheet" />
+    </LinearLayout>
+
+</FrameLayout>
+
diff --git a/nearby/halfsheet/res/values/strings.xml b/nearby/halfsheet/res/values/strings.xml
new file mode 100644
index 0000000..22f78d7
--- /dev/null
+++ b/nearby/halfsheet/res/values/strings.xml
@@ -0,0 +1,19 @@
+<!--
+  ~ Copyright (C) 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.
+  -->
+
+<resources>
+    <string name="app_name">Nearby HalfSheet Dialog</string>
+</resources>
\ No newline at end of file
diff --git a/nearby/halfsheet/src/com/android/nearby/halfsheet/HalfSheetActivity.java b/nearby/halfsheet/src/com/android/nearby/halfsheet/HalfSheetActivity.java
new file mode 100644
index 0000000..4a74c9b
--- /dev/null
+++ b/nearby/halfsheet/src/com/android/nearby/halfsheet/HalfSheetActivity.java
@@ -0,0 +1,48 @@
+/*
+ * Copyright (C) 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.nearby.halfsheet;
+
+import static com.android.server.nearby.fastpair.Constant.EXTRA_BINDER;
+import static com.android.server.nearby.fastpair.Constant.EXTRA_BUNDLE;
+
+import android.app.Activity;
+import android.nearby.IFastPairHalfSheetCallback;
+import android.os.Bundle;
+import android.os.RemoteException;
+import android.util.Log;
+
+import androidx.annotation.Nullable;
+
+/**
+ * Half sheet activity to show pairing ux.
+ */
+public class HalfSheetActivity extends Activity {
+    @Override
+    protected void onCreate(@Nullable Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        setContentView(R.layout.activity_half_sheet);
+        Bundle bundle = getIntent().getBundleExtra(EXTRA_BUNDLE);
+        // Any app that has the component name can start the activity so the binder can't be
+        // trusted.
+        try {
+            IFastPairHalfSheetCallback.Stub.asInterface(bundle.getBinder(EXTRA_BINDER))
+                    .onHalfSheetConnectionConfirm();
+        } catch (RemoteException e) {
+            Log.d("FastPairHalfSheet", "invoke callback fall");
+        }
+    }
+}
diff --git a/nearby/service/Android.bp b/nearby/service/Android.bp
index bc3f91d..63e2748 100644
--- a/nearby/service/Android.bp
+++ b/nearby/service/Android.bp
@@ -23,6 +23,20 @@
     ],
 }
 
+filegroup {
+    name: "nearby-service-string-res",
+    srcs: [
+        "java/**/Constant.java",
+    ],
+}
+
+java_library {
+    name: "nearby-service-string",
+    srcs: [":nearby-service-string-res"],
+    sdk_version: "module_current",
+}
+
+
 // Main lib for nearby services.
 java_library {
     name: "service-nearby",
diff --git a/nearby/service/java/com/android/server/nearby/fastpair/Constant.java b/nearby/service/java/com/android/server/nearby/fastpair/Constant.java
new file mode 100644
index 0000000..bf73360
--- /dev/null
+++ b/nearby/service/java/com/android/server/nearby/fastpair/Constant.java
@@ -0,0 +1,25 @@
+/*
+ * Copyright (C) 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.server.nearby.fastpair;
+
+/**
+ * String constant for half sheet.
+ */
+public class Constant {
+    public static final String EXTRA_BINDER = "com.android.server.nearby.fastpair.BINDER";
+    public static final String EXTRA_BUNDLE = "com.android.server.nearby.fastpair.BUNDLE_EXTRA";
+}
diff --git a/nearby/service/java/com/android/server/nearby/fastpair/FastPairManager.java b/nearby/service/java/com/android/server/nearby/fastpair/FastPairManager.java
index ff4bce2..56650ce 100644
--- a/nearby/service/java/com/android/server/nearby/fastpair/FastPairManager.java
+++ b/nearby/service/java/com/android/server/nearby/fastpair/FastPairManager.java
@@ -16,17 +16,29 @@
 
 package com.android.server.nearby.fastpair;
 
+import static com.android.server.nearby.fastpair.Constant.EXTRA_BINDER;
+import static com.android.server.nearby.fastpair.Constant.EXTRA_BUNDLE;
+
 import android.annotation.Nullable;
 import android.annotation.WorkerThread;
 import android.app.KeyguardManager;
 import android.bluetooth.BluetoothAdapter;
 import android.bluetooth.BluetoothManager;
 import android.content.BroadcastReceiver;
+import android.content.ComponentName;
 import android.content.Context;
 import android.content.Intent;
 import android.content.IntentFilter;
+import android.content.pm.PackageManager;
+import android.content.pm.ResolveInfo;
+import android.nearby.NearbyDevice;
+import android.nearby.ScanCallback;
+import android.os.Bundle;
+import android.os.UserHandle;
 import android.util.Log;
 
+import androidx.annotation.NonNull;
+
 import com.android.server.nearby.common.bluetooth.BluetoothException;
 import com.android.server.nearby.common.bluetooth.fastpair.FastPairConnection;
 import com.android.server.nearby.common.bluetooth.fastpair.FastPairDualConnection;
@@ -42,9 +54,12 @@
 import com.android.server.nearby.fastpair.cache.DiscoveryItem;
 import com.android.server.nearby.fastpair.cache.FastPairCacheManager;
 import com.android.server.nearby.fastpair.footprint.FootprintsDeviceManager;
+import com.android.server.nearby.fastpair.halfsheet.HalfSheetCallback;
 import com.android.server.nearby.fastpair.pairinghandler.PairingProgressHandlerBase;
+import com.android.server.nearby.util.Environment;
 
 import java.security.GeneralSecurityException;
+import java.util.List;
 import java.util.concurrent.ExecutionException;
 import java.util.concurrent.Executor;
 import java.util.concurrent.ExecutorService;
@@ -52,6 +67,7 @@
 import java.util.concurrent.Future;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.TimeoutException;
+import java.util.stream.Collectors;
 
 import service.proto.Rpcs;
 
@@ -63,13 +79,18 @@
 public class FastPairManager {
     private static final String ACTION_PREFIX = UserActionHandler.PREFIX;
     private static final int WAIT_FOR_UNLOCK_MILLIS = 5000;
+    private static final String ACTIVITY_INTENT_ACTION = "android.nearby.SHOW_HALFSHEET";
     /** A notification ID which should be dismissed*/
     public static final String EXTRA_NOTIFICATION_ID = ACTION_PREFIX + "EXTRA_NOTIFICATION_ID";
+    public static final String ACTION_RESOURCES_APK = "android.nearby.SHOW_HALFSHEET";
+
     private static Executor sFastPairExecutor;
 
-    LocatorContextWrapper mLocatorContextWrapper;
-    IntentFilter mIntentFilter;
-    Locator mLocator;
+    private String mHalfSheetApkPkgName;
+
+    final LocatorContextWrapper mLocatorContextWrapper;
+    final IntentFilter mIntentFilter;
+    final Locator mLocator;
     private final BroadcastReceiver mScreenBroadcastReceiver = new BroadcastReceiver() {
         @Override
         public void onReceive(Context context, Intent intent) {
@@ -91,12 +112,29 @@
                 Rpcs.GetObservedDeviceResponse.newBuilder().build();
     }
 
+    final ScanCallback mScanCallback = new ScanCallback() {
+        @Override
+        public void onDiscovered(@NonNull NearbyDevice device) {
+            Log.d("FastPair", "Ondiscovery " + device.getName());
+        }
+
+        @Override
+        public void onUpdated(@NonNull NearbyDevice device) {
+
+        }
+
+        @Override
+        public void onLost(@NonNull NearbyDevice device) {
+
+        }
+    };
     /**
      * Function called when nearby service start.
      */
     public void initiate() {
         mIntentFilter.addAction(Intent.ACTION_SCREEN_ON);
         mIntentFilter.addAction(Intent.ACTION_SCREEN_OFF);
+
         mLocatorContextWrapper.getContext()
                 .registerReceiver(mScreenBroadcastReceiver, mIntentFilter);
 
@@ -110,7 +148,6 @@
         mLocatorContextWrapper.getContext().unregisterReceiver(mScreenBroadcastReceiver);
     }
 
-
     /**
      * Starts fast pair process.
      */
@@ -251,6 +288,9 @@
         }
     }
 
+    /**
+     * This function should only be called on main thread since there is no lock
+     */
     private static Executor getExecutor() {
         if (sFastPairExecutor != null) {
             return sFastPairExecutor;
@@ -267,4 +307,64 @@
         BluetoothManager manager = context.getSystemService(BluetoothManager.class);
         return manager == null ? null : manager.getAdapter();
     }
+
+    /** Gets the package name of HalfSheet.apk
+     * getHalfSheetApkPkgName may invoke PackageManager multiple times and it does not have
+     * race condition check. Since there is no lock for mHalfSheetApkPkgName.
+     */
+    String getHalfSheetApkPkgName() {
+        if (mHalfSheetApkPkgName != null) {
+            return mHalfSheetApkPkgName;
+        }
+        List<ResolveInfo> resolveInfos = mLocatorContextWrapper.getContext()
+                .getPackageManager().queryIntentActivities(
+                new Intent(ACTION_RESOURCES_APK),
+                PackageManager.MATCH_SYSTEM_ONLY);
+
+        // remove apps that don't live in the nearby apex
+        resolveInfos.removeIf(info ->
+                !Environment.isAppInNearbyApex(info.activityInfo.applicationInfo));
+
+        if (resolveInfos.isEmpty()) {
+            // Resource APK not loaded yet, print a stack trace to see where this is called from
+            Log.e("FastPairManager", "Attempted to fetch resources before halfsheet "
+                            + " APK is installed or package manager can't resolve correctly!",
+                    new IllegalStateException());
+            return null;
+        }
+
+        if (resolveInfos.size() > 1) {
+            // multiple apps found, log a warning, but continue
+            Log.w("FastPairManager", "Found > 1 APK that can resolve halfsheet APK intent: "
+                    + resolveInfos.stream()
+                    .map(info -> info.activityInfo.applicationInfo.packageName)
+                    .collect(Collectors.joining(", ")));
+        }
+
+        // Assume the first ResolveInfo is the one we're looking for
+        ResolveInfo info = resolveInfos.get(0);
+        mHalfSheetApkPkgName = info.activityInfo.applicationInfo.packageName;
+        Log.i("FastPairManager", "Found halfsheet APK at: " + mHalfSheetApkPkgName);
+        return mHalfSheetApkPkgName;
+    }
+
+    /**
+     * Invokes half sheet in the other apk. This function can only be called in Nearby because other
+     * app can't get the correct component name.
+     */
+    void showHalfSheet() {
+        if (mLocatorContextWrapper != null) {
+            String packageName = getHalfSheetApkPkgName();
+            HalfSheetCallback callback = new HalfSheetCallback();
+            Bundle bundle = new Bundle();
+            bundle.putBinder(EXTRA_BINDER, callback);
+            mLocatorContextWrapper.getContext()
+                    .startActivityAsUser(new Intent(ACTIVITY_INTENT_ACTION)
+                                    .putExtra(EXTRA_BUNDLE, bundle)
+                                    .setComponent(new ComponentName(packageName,
+                                            packageName + ".HalfSheetActivity")),
+                            UserHandle.CURRENT);
+
+        }
+    }
 }
diff --git a/nearby/service/java/com/android/server/nearby/fastpair/halfsheet/HalfSheetCallback.java b/nearby/service/java/com/android/server/nearby/fastpair/halfsheet/HalfSheetCallback.java
new file mode 100644
index 0000000..fd9e460
--- /dev/null
+++ b/nearby/service/java/com/android/server/nearby/fastpair/halfsheet/HalfSheetCallback.java
@@ -0,0 +1,30 @@
+/*
+ * Copyright (C) 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.server.nearby.fastpair.halfsheet;
+
+import android.nearby.IFastPairHalfSheetCallback;
+import android.util.Log;
+
+/**
+ * Callback to send ux action back to nearby service.
+ */
+public class HalfSheetCallback  extends IFastPairHalfSheetCallback.Stub {
+    @Override
+    public void onHalfSheetConnectionConfirm() {
+        Log.d("FastPairHalfSheet", "Call back receiver");
+    }
+}
diff --git a/nearby/service/java/com/android/server/nearby/util/Environment.java b/nearby/service/java/com/android/server/nearby/util/Environment.java
new file mode 100644
index 0000000..dc131e7
--- /dev/null
+++ b/nearby/service/java/com/android/server/nearby/util/Environment.java
@@ -0,0 +1,63 @@
+/*
+ * Copyright (C) 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.server.nearby.util;
+
+import android.content.ApexEnvironment;
+import android.content.pm.ApplicationInfo;
+import android.os.UserHandle;
+
+import java.io.File;
+
+/**
+ * Provides function to make sure the function caller is from the same apex.
+ */
+public class Environment {
+    /**
+     * NEARBY apex name.
+     */
+    private static final String NEARBY_APEX_NAME = "com.android.nearby";
+
+    /**
+     * The path where the Nearby apex is mounted.
+     * Current value = "/apex/com.android.nearby"
+     */
+    private static final String NEARBY_APEX_PATH =
+            new File("/apex", NEARBY_APEX_NAME).getAbsolutePath();
+
+    /**
+     * Nearby shared folder.
+     */
+    public static File getNearbyDirectory() {
+        return ApexEnvironment.getApexEnvironment(NEARBY_APEX_NAME).getDeviceProtectedDataDir();
+    }
+
+    /**
+     * Nearby user specific folder.
+     */
+    public static File getNearbyDirectory(int userId) {
+        return ApexEnvironment.getApexEnvironment(NEARBY_APEX_NAME)
+                .getCredentialProtectedDataDirForUser(UserHandle.of(userId));
+    }
+
+    /**
+     * Returns true if the app is in the nearby apex, false otherwise.
+     * Checks if the app's path starts with "/apex/com.android.nearby".
+     */
+    public static boolean isAppInNearbyApex(ApplicationInfo appInfo) {
+        return appInfo.sourceDir.startsWith(NEARBY_APEX_PATH);
+    }
+}