Use this guide to quickly start a basic one-to-one voice call with the Agora SDK for Unity.

Sample project

We provide an open-source Hello-Unity3D-Agora sample project on GitHub that implements the basic one-to-one voice call. You can also see how to run the sample project in Add voice chat to your Unity app on Android and iOS.


  • Unity 2017 or later

  • Operating system and IDE requirements:

    Target Platform Operating system version IDE version
    Android Android 4.1 or later Android Studio 2.0 or later
    iOS iOS 8.0 or later Xcode 8.0 or later
    macOS macOS 10.0 or later Xcode 8.0 or later
    Windows Windows XP SP3 or later Visual Studio 2013 or later
  • A valid Agora account and an App ID

Open the specified ports in Firewall Requirements if your network has a firewall.

Set up the development environment

In this section, we create a Unity project and integrate the SDK into the project.

Create a Unity project

Use the following steps or follow the Unity official manual to build a project from scratch. Skip to Integrate the SDK if you have already created a Unity project.

Create a Unity Project
  1. Ensure that you have downloaded and installed Unity before the following steps. If not, click here to download.

  2. Open Unity and click New.

  3. Fill in and select the options in the following fields, and click Create project.

    • Project name
    • Location
    • Organization
    • Template: Choose 3D

Integrate the SDK

Choose either of the following approaches to integrate the Agora Unity SDK into your project.

Approach 1: Automatically integrate the SDK with Unity Asset Store

  1. Open Asset Store in Unity, search for Agora Voice SDK for Unity and click it.
  2. Click Download to download the SDK.
  3. When the download completes, the button becomes Import. Click Import to show the packages of the downloaded SDK.
  4. All packages of the SDK are chosen by default. Uncheck the packages you do not need and click Import.

Approach 2: Manually add the SDK files

  1. Go to SDK Downloads, download the Agora SDK for Unity under Voice SDK, and unzip the downloaded SDK package.

  2. Create a Plugins folder under the Assets folder in your project.

  3. Copy the following file or subfolder from the libs folder of the downloaded SDK to the corresponding directory of your project.

    Target Platform File or subfolder Directory of your project
    Android /Android/AgoraRtcEngineKit.plugin /Assets/Plugins/Android
    iOS /iOS/AgoraAudioKit.framework /Assets/Plugins/iOS
    macOS /macOS/agoraSdkCWrapper.bundle /Assets/Plugins/macOS
    Windows /x86 /Assets/Plugins/x86
    Windows /x86_64 /Assets/Plugins/x86_64
    • Android or iOS developers using Unity Editor for macOS or Windows must also copy the SDK file for macOS or the subfolder for Windows X86_64 to the specified directory.
    • Android developers also need to copy the AndroidManifest.xml and from the directory of the sample project (./Assets/Plugins/Android/AgoraRtcEngineKit.plugin) to the directory of the Unity project (./Assets/Plugins/Android). The former is for adding project permissions; the latter is for setting project properties.
    • When integrate the SDK with the version earlier than v3.0.1, iOS developers also need to do the following steps: (You can find the sample code logic in BL_BuildPostProcess.cs, or copy this file to directory of your Unity project)
      • Link the following libraries:
        • CoreTelephony.framework
        • libresolv.tbd
        • libiPhone-lib.a
        • CoreText.framework
        • CoreML.framework
        • Accelerate.framework
      • Ask for the following permissios: NSMicrophoneUsageDescription

Implement a basic voice call

This section provides instructions on using the Agora Voice SDK for Unity to implement a basic one-to-one voice call, as well as an API call sequence diagram.

1. Create the UI

Create the user interface (UI) for a voice call in your project. If you already have one UI in your project, skip to Get the device permission (Android only) or Initialize IRtcEngine.

We recommend adding the following elements to the UI:

  • An enter button
  • An exit button

2. Get the device permission (Android only)

If you build for Android, you should add in APIs to check and request the device permission. For all other platforms, this is handled by the engine, and you can skip to Initialize IRtcEngine.

Unity versions later than UNITY_2018_3_OR_NEWER do not automatically request microphone permissions from your Android device. If you are using one of these versions, call the CheckPermission method to request access to the microphone of your Android device.

using UnityEngine.Android; 
void Start () 
private void CheckPermission()
foreach(string permission in permissionList) 
if (Permission.HasUserAuthorizedPermission(permission)) 
void Update () 
// Ask for your Android device's permissions.

3. Initialize IRtcEngine

Initialize the IRtcEngine object before calling any other Agora APIs.

Call the GetEngine method and pass in the App ID to initialize the IRtcEngine object.

If you want to exit the app or release the memory of IRtcEngine, call Destroy to destroy the IRtcEngine object. See details in Destroy the IRtcEngine object.

Listen for callback events, such as when the local user joins the channel, and when the first audio frame of a remote user is decoded.

// Pass an App ID to create and initialize an IRtcEngine object.
mRtcEngine = IRtcEngine.GetEngine (appId); 
// Listen for the OnJoinChannelSuccessHandler callback.
// This callback occurs when the local user successfully joins the channel.
mRtcEngine.OnJoinChannelSuccessHandler = OnJoinChannelSuccessHandler; 
// Listen for the OnUserJoinedHandler callback.
// This callback occurs when the first audio frame of a remote user is received and decoded after the remote user successfully joins the channel.
mRtcEngine.OnUserJoinedHandler = OnUserJoinedHandler; 
// Listen for the OnUserOfflineHandler callback.
// This callback occurs when the remote user leaves the channel or drops offline.
mRtcEngine.OnUserOfflineHandler = OnUserOfflineHandler;

4. Join a channel

After initializing the IRtcEngine object, you can call JoinChannelByKey to join a channel. Set the following parameters when calling this method::

  • channelKey: The token for identifying the role and privileges of a user. Set it as one of the following values:

    • NULL.
    • A temporary token generated in Agora Console. A temporary token is valid for 24 hours. For details, see Get a temporary token.
    • A token generated at the server. This applies to scenarios with high-security requirements. For details, see Generate a token from Your Server.
    If your project has enabled the app certificate, ensure that you provide a token.
  • channelName: The unique name of the channel to join. Users that input the same channel name join the same channel.

  • uid: Integer. The unique ID of the local user. If you set uid as 0, the SDK automatically assigns one user ID and returns it in the OnJoinChannelSuccessHandler callback.

// Join a channel. 
mRtcEngine.JoinChannelByKey(null, channel, null, 0);

5. Leave the channel

According to your scenario, such as when the call ends and when you need to close the app, call LeaveChannel to leave the current call.

public void leave()
        Debug.Log ("calling leave");
        if (mRtcEngine == null)
        // Leave the channel.

6. Destroy the IRtcEngine object

After leaving the channel, if you want to exit the app or release the memory of IRtcEngine, call Destroy to destroy the IRtcEngine object.

void OnApplicationQuit()
    if (mRtcEngine != null)
    // Destroy the IRtcEngine object.
    mRtcEngine = null;

Run the project

Run the project in Unity. You can hear the voice of both the local and remote users when you successfully start a one-to-one voice call in the app.