diff --git a/PLDroidMediaStreamingDemo/app/build.gradle b/PLDroidMediaStreamingDemo/app/build.gradle
index 668f8d8..8befc54 100644
--- a/PLDroidMediaStreamingDemo/app/build.gradle
+++ b/PLDroidMediaStreamingDemo/app/build.gradle
@@ -2,14 +2,14 @@ apply plugin: 'com.android.application'
 
 android {
     compileSdkVersion 29
-    buildToolsVersion '28.0.3'
+    buildToolsVersion '29.0.3'
 
     defaultConfig {
         applicationId "com.qiniu.pili.droid.streaming.demo"
-        minSdkVersion 16
+        minSdkVersion 18
         targetSdkVersion 29
-        versionCode 71
-        versionName "3.0.1"
+        versionCode 72
+        versionName "3.0.2"
     }
     buildTypes {
         release {
@@ -22,17 +22,19 @@ android {
 dependencies {
     // 文件选择 jar 包，非必须
     implementation 'com.github.angads25:filepicker:1.0.6'
-    // dns 相关 jar 包，若无需自定义 DNS 配置，则无需依赖
-    implementation 'com.qiniu:happy-dns:0.2.16'
+    // dns 相关 jar 包，必须依赖
+    implementation 'com.qiniu:happy-dns:0.2.17'
+    // 监听应用生命周期，必须依赖
+    implementation 'android.arch.lifecycle:extensions:1.1.1'
     // 扫码相关 jar 包，非必须
     implementation 'com.journeyapps:zxing-android-embedded:3.0.2@aar'
-    implementation 'com.google.zxing:core:3.2.0'
+    implementation 'com.google.zxing:core:3.3.3'
     implementation 'com.android.support:appcompat-v7:28.0.0'
 
     if (buildWithCameraStreamingLibrary) {
         implementation project(':library')
     } else {
         // 推流 SDK jar 包，为推流 SDK 必须依赖的库
-        implementation files('libs/pldroid-media-streaming-3.0.1.jar')
+        implementation files('libs/pldroid-media-streaming-3.0.2.jar')
     }
 }
diff --git a/PLDroidMediaStreamingDemo/app/libs/pldroid-media-streaming-3.0.1.jar b/PLDroidMediaStreamingDemo/app/libs/pldroid-media-streaming-3.0.1.jar
deleted file mode 100644
index 8f94d3c..0000000
Binary files a/PLDroidMediaStreamingDemo/app/libs/pldroid-media-streaming-3.0.1.jar and /dev/null differ
diff --git a/PLDroidMediaStreamingDemo/app/libs/pldroid-media-streaming-3.0.2.jar b/PLDroidMediaStreamingDemo/app/libs/pldroid-media-streaming-3.0.2.jar
new file mode 100644
index 0000000..3a8f711
Binary files /dev/null and b/PLDroidMediaStreamingDemo/app/libs/pldroid-media-streaming-3.0.2.jar differ
diff --git a/PLDroidMediaStreamingDemo/app/src/main/AndroidManifest.xml b/PLDroidMediaStreamingDemo/app/src/main/AndroidManifest.xml
index 4e3287a..5a02f31 100644
--- a/PLDroidMediaStreamingDemo/app/src/main/AndroidManifest.xml
+++ b/PLDroidMediaStreamingDemo/app/src/main/AndroidManifest.xml
@@ -13,7 +13,7 @@
 
     <uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
     <uses-permission android:name="android.permission.READ_PHONE_STATE" />
-    <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
+    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
     <uses-permission android:name="android.permission.FOREGROUND_SERVICE" />
 
     <uses-feature android:name="android.hardware.camera.autofocus" />
diff --git a/PLDroidMediaStreamingDemo/app/src/main/java/com/qiniu/pili/droid/streaming/demo/StreamingApplication.java b/PLDroidMediaStreamingDemo/app/src/main/java/com/qiniu/pili/droid/streaming/demo/StreamingApplication.java
index ec9b901..fe98447 100644
--- a/PLDroidMediaStreamingDemo/app/src/main/java/com/qiniu/pili/droid/streaming/demo/StreamingApplication.java
+++ b/PLDroidMediaStreamingDemo/app/src/main/java/com/qiniu/pili/droid/streaming/demo/StreamingApplication.java
@@ -6,6 +6,7 @@
 import com.qiniu.pili.droid.streaming.StreamingEnv;
 import com.qiniu.pili.droid.streaming.demo.service.KeepAppAliveService;
 import com.qiniu.pili.droid.streaming.demo.utils.AppStateTracker;
+import com.qiniu.pili.droid.streaming.demo.utils.Util;
 
 public class StreamingApplication extends Application {
 
@@ -17,8 +18,10 @@ public void onCreate() {
         super.onCreate();
         /**
          * init must be called before any other func
+         *
+         * 注意：参数 userId 代表用户的唯一标识符，用于区分不同的用户
          */
-        StreamingEnv.init(getApplicationContext());
+        StreamingEnv.init(getApplicationContext(), Util.getUserId(getApplicationContext()));
 
         /**
          * track app background state to avoid possibly stopping microphone recording
diff --git a/PLDroidMediaStreamingDemo/app/src/main/java/com/qiniu/pili/droid/streaming/demo/activity/AVStreamingActivity.java b/PLDroidMediaStreamingDemo/app/src/main/java/com/qiniu/pili/droid/streaming/demo/activity/AVStreamingActivity.java
index 7a043c3..70e45d9 100644
--- a/PLDroidMediaStreamingDemo/app/src/main/java/com/qiniu/pili/droid/streaming/demo/activity/AVStreamingActivity.java
+++ b/PLDroidMediaStreamingDemo/app/src/main/java/com/qiniu/pili/droid/streaming/demo/activity/AVStreamingActivity.java
@@ -396,6 +396,15 @@ private void initStreamingManager() {
         if (mCameraConfig.mIsCustomFaceBeauty) {
             mMediaStreamingManager.setSurfaceTextureCallback(mSurfaceTextureCallback);
         }
+        mMediaStreamingManager.setCameraErrorCallback(new Camera.ErrorCallback() {
+            @Override
+            public void onError(int errorCode, Camera camera) {
+                // 摄像头被其他应用抢占时触发
+                if (errorCode == Camera.CAMERA_ERROR_EVICTED) {
+                    Log.e(TAG, "camera was evicted by the other app!");
+                }
+            }
+        });
 
         mAudioMixer = mMediaStreamingManager.getAudioMixer();
         mAudioMixer.setOnAudioMixListener(new OnAudioMixListener() {
@@ -885,6 +894,25 @@ public void run() {
                         }
                     });
                     break;
+                case START_VIDEO_ENCODER_FAIL:
+                case VIDEO_ENCODER_ERROR:
+                case START_AUDIO_ENCODER_FAIL:
+                case AUDIO_ENCODER_ERROR:
+                    /**
+                     * 当回调 START_VIDEO_ENCODER_FAIL、VIDEO_ENCODER_ERROR、START_AUDIO_ENCODER_FAIL、
+                     * AUDIO_ENCODER_ERROR 等状态时，代表编码器出现异常，推流已停止，相应资源也已释放，
+                     * 如果需要，可以基于报错的编码器进行重新配置，更新 {@link AVCodecType} 之后，重新开启推流
+                     */
+                    mIsStreaming = false;
+                    mStatusMsgContent = getString(R.string.string_state_ready);
+                    runOnUiThread(new Runnable() {
+                        @Override
+                        public void run() {
+                            mControlFragment.setShutterButtonPressed(false);
+                            Toast.makeText(AVStreamingActivity.this, "编码器错误！！！", Toast.LENGTH_SHORT).show();
+                        }
+                    });
+                    break;
                 case IOERROR:
                     /**
                      * 在 `startStreaming` 时，如果网络不可用，则会回调此状态
@@ -972,7 +1000,7 @@ public boolean onRecordAudioFailedHandled(int code) {
         public boolean onRestartStreamingHandled(int code) {
             Log.i(TAG, "onRestartStreamingHandled");
             startStreamingInternal(2000);
-            return false;
+            return true;
         }
 
         /**
diff --git a/PLDroidMediaStreamingDemo/app/src/main/java/com/qiniu/pili/droid/streaming/demo/activity/ImportStreamingActivity.java b/PLDroidMediaStreamingDemo/app/src/main/java/com/qiniu/pili/droid/streaming/demo/activity/ImportStreamingActivity.java
index 4b4e503..19d0c15 100644
--- a/PLDroidMediaStreamingDemo/app/src/main/java/com/qiniu/pili/droid/streaming/demo/activity/ImportStreamingActivity.java
+++ b/PLDroidMediaStreamingDemo/app/src/main/java/com/qiniu/pili/droid/streaming/demo/activity/ImportStreamingActivity.java
@@ -6,7 +6,6 @@
 import android.os.Bundle;
 import android.os.Handler;
 import android.os.HandlerThread;
-import android.os.Looper;
 import android.util.Log;
 import android.view.SurfaceView;
 import android.view.View;
@@ -392,6 +391,24 @@ public void onStateChanged(StreamingState streamingState, Object extra) {
                 case UNAUTHORIZED_PACKAGE:
                     mLogContent += "Unauthorized package\n";
                     break;
+                case START_VIDEO_ENCODER_FAIL:
+                case VIDEO_ENCODER_ERROR:
+                case START_AUDIO_ENCODER_FAIL:
+                case AUDIO_ENCODER_ERROR:
+                    /**
+                     * 当回调 START_VIDEO_ENCODER_FAIL、VIDEO_ENCODER_ERROR、START_AUDIO_ENCODER_FAIL、
+                     * AUDIO_ENCODER_ERROR 等状态时，代表编码器出现异常，推流已停止，相应资源也已释放，
+                     * 如果需要，可以基于报错的编码器进行重新配置，更新 {@link AVCodecType} 之后，重新开启推流
+                     */
+                    mStatusMsgContent = getString(R.string.string_state_ready);
+                    setShutterButtonEnabled(true);
+                    runOnUiThread(new Runnable() {
+                        @Override
+                        public void run() {
+                            Toast.makeText(ImportStreamingActivity.this, "编码器错误！！！", Toast.LENGTH_SHORT).show();
+                        }
+                    });
+                    break;
             }
             runOnUiThread(new Runnable() {
                 @Override
diff --git a/PLDroidMediaStreamingDemo/app/src/main/java/com/qiniu/pili/droid/streaming/demo/utils/Config.java b/PLDroidMediaStreamingDemo/app/src/main/java/com/qiniu/pili/droid/streaming/demo/utils/Config.java
index 43a3771..53411dd 100644
--- a/PLDroidMediaStreamingDemo/app/src/main/java/com/qiniu/pili/droid/streaming/demo/utils/Config.java
+++ b/PLDroidMediaStreamingDemo/app/src/main/java/com/qiniu/pili/droid/streaming/demo/utils/Config.java
@@ -16,4 +16,7 @@ public class Config {
     public static final String PUBLISH_URL = "PUBLISH_URL";
     public static final String TRANSFER_MODE_QUIC = "TRANSFER_MODE_QUIC";
     public static final String AUDIO_CHANNEL_STEREO = "AUDIO_CHANNEL_STEREO";
+
+    public static final String SP_NAME = "PLDroidMediaStreamingDemo";
+    public static final String KEY_USER_ID = "userId";
 }
diff --git a/PLDroidMediaStreamingDemo/app/src/main/java/com/qiniu/pili/droid/streaming/demo/utils/PermissionChecker.java b/PLDroidMediaStreamingDemo/app/src/main/java/com/qiniu/pili/droid/streaming/demo/utils/PermissionChecker.java
index 9a16311..6cd38d5 100644
--- a/PLDroidMediaStreamingDemo/app/src/main/java/com/qiniu/pili/droid/streaming/demo/utils/PermissionChecker.java
+++ b/PLDroidMediaStreamingDemo/app/src/main/java/com/qiniu/pili/droid/streaming/demo/utils/PermissionChecker.java
@@ -56,8 +56,14 @@ public boolean checkPermission() {
         if (!addPermission(permissionsList, Manifest.permission.WRITE_EXTERNAL_STORAGE)) {
             permissionsNeeded.add("Write external storage");
         }
+        if (!addPermission(permissionsList, Manifest.permission.READ_PHONE_STATE)) {
+            permissionsNeeded.add("Read phone state");
+        }
+        if (!addPermission(permissionsList, Manifest.permission.ACCESS_FINE_LOCATION)) {
+            permissionsNeeded.add("Access fine location");
+        }
 
-        if (permissionsNeeded.size() > 0) {
+        if (!permissionsNeeded.isEmpty()) {
             // Need Rationale
             String message = "You need to grant access to " + permissionsNeeded.get(0);
             for (int i = 1; i < permissionsNeeded.size(); i++) {
diff --git a/PLDroidMediaStreamingDemo/app/src/main/java/com/qiniu/pili/droid/streaming/demo/utils/Util.java b/PLDroidMediaStreamingDemo/app/src/main/java/com/qiniu/pili/droid/streaming/demo/utils/Util.java
index bf7a7b0..6a1bc2e 100644
--- a/PLDroidMediaStreamingDemo/app/src/main/java/com/qiniu/pili/droid/streaming/demo/utils/Util.java
+++ b/PLDroidMediaStreamingDemo/app/src/main/java/com/qiniu/pili/droid/streaming/demo/utils/Util.java
@@ -2,6 +2,7 @@
 
 import android.app.Activity;
 import android.content.Context;
+import android.content.SharedPreferences;
 import android.os.Build;
 import android.widget.Toast;
 
@@ -17,6 +18,7 @@
 import java.net.HttpURLConnection;
 import java.net.InetAddress;
 import java.net.URL;
+import java.util.Random;
 
 public class Util {
 
@@ -87,4 +89,21 @@ public static DnsManager getMyDnsManager(Context context) {
         }
         return new DnsManager(NetworkInfo.normal, new IResolver[]{r0, r1, r2});
     }
+
+    public static String getUserId(Context context) {
+        SharedPreferences preferences = context.getSharedPreferences(Config.SP_NAME, Context.MODE_PRIVATE);
+        String userId = preferences.getString(Config.KEY_USER_ID, "");
+        if ("".equals(userId)) {
+            userId = userId();
+            SharedPreferences.Editor editor = preferences.edit();
+            editor.putString(Config.KEY_USER_ID, userId);
+            editor.apply();
+        }
+        return userId;
+    }
+
+    private static String userId() {
+        Random r = new Random();
+        return System.currentTimeMillis() + "" + r.nextInt(999);
+    }
 }
diff --git a/PLDroidMediaStreamingDemo/app/src/main/jniLibs/arm64-v8a/libpldroid_streaming_core.so b/PLDroidMediaStreamingDemo/app/src/main/jniLibs/arm64-v8a/libpldroid_streaming_core.so
index f36cfba..b880ee3 100755
Binary files a/PLDroidMediaStreamingDemo/app/src/main/jniLibs/arm64-v8a/libpldroid_streaming_core.so and b/PLDroidMediaStreamingDemo/app/src/main/jniLibs/arm64-v8a/libpldroid_streaming_core.so differ
diff --git a/PLDroidMediaStreamingDemo/app/src/main/jniLibs/armeabi-v7a/libpldroid_streaming_core.so b/PLDroidMediaStreamingDemo/app/src/main/jniLibs/armeabi-v7a/libpldroid_streaming_core.so
index 3c4f704..be2a2b8 100755
Binary files a/PLDroidMediaStreamingDemo/app/src/main/jniLibs/armeabi-v7a/libpldroid_streaming_core.so and b/PLDroidMediaStreamingDemo/app/src/main/jniLibs/armeabi-v7a/libpldroid_streaming_core.so differ
diff --git a/PLDroidMediaStreamingDemo/app/src/main/jniLibs/armeabi/libpldroid_streaming_core.so b/PLDroidMediaStreamingDemo/app/src/main/jniLibs/armeabi/libpldroid_streaming_core.so
index e285e32..703880c 100755
Binary files a/PLDroidMediaStreamingDemo/app/src/main/jniLibs/armeabi/libpldroid_streaming_core.so and b/PLDroidMediaStreamingDemo/app/src/main/jniLibs/armeabi/libpldroid_streaming_core.so differ
diff --git a/PLDroidMediaStreamingDemo/app/src/main/jniLibs/x86/libpldroid_streaming_core.so b/PLDroidMediaStreamingDemo/app/src/main/jniLibs/x86/libpldroid_streaming_core.so
index bf7c271..3a1015c 100755
Binary files a/PLDroidMediaStreamingDemo/app/src/main/jniLibs/x86/libpldroid_streaming_core.so and b/PLDroidMediaStreamingDemo/app/src/main/jniLibs/x86/libpldroid_streaming_core.so differ
diff --git a/README.md b/README.md
index 16b8615..3cfa8ff 100644
--- a/README.md
+++ b/README.md
@@ -39,15 +39,19 @@ PLDroidCameraStreaming 是一个适用于 Android 的 RTMP 直播推流 SDK，
 ## 设备以及系统要求
 
 - 设备要求：搭载 Android 系统的设备
-- 系统要求：Android 4.0.3(API 15) 及其以上
+- 系统要求：Android 4.3(API 18) 及其以上
 
 ## 版本升级须知
 
+### v3.0.2
+- 从 v3.0.2 版本开始，请务必添加 `android.arch.lifecycle:extensions:x.y.z` 的依赖
+- 从 v3.0.2 版本开始，`StreamingEnv.init(Context context)` 已被弃用，请更新到 `StreamingEnv.init(Context contex, String userId)` 进行环境的初始化，其中，userId 代表用户的唯一标识符，用于区分不同的用户
+
 ### v3.0.1
-- 从 3.0.1 版本开始，如果您使用了 Happy DNS 库，建议升级到 0.2.16 版本
+- 从 v3.0.1 版本开始，如果您使用了 Happy DNS 库，请务必升级到 0.2.17 版本
 
 ### v3.0.0
-- **从 v3.0.0 版本开始，七牛直播推流 SDK 需要先获取授权才能使用。授权分为试用版和正式版，可通过 400-808-9176 转 1 号线联系七牛商务咨询，或者 [通过工单](https://support.qiniu.com/?ref=developer.qiniu.com) 联系七牛的技术支持。**
+- **从 v3.0.0 版本开始，七牛直播推流 SDK 需要先获取授权才能使用。授权分为试用版和正式版，可通过 400-808-9176 转 2 号线联系七牛商务咨询，或者 [通过工单](https://support.qiniu.com/?ref=developer.qiniu.com) 联系七牛的技术支持。**
 - **v3.0.0 之前的版本不受影响，请继续放心使用。**
 - **老客户升级 v3.0.0 版本之前，请先联系七牛获取相应授权，以免发生鉴权不通过的现象。**
 - 基于 114 dns 解析的不确定性，使用该解析可能会导致解析的网络 ip 无法做到最大的优化策略，进而出现推流质量不佳的现象。因此建议使用非 114 dns 解析
diff --git a/ReleaseNotes/release-notes-3.0.2.md b/ReleaseNotes/release-notes-3.0.2.md
new file mode 100644
index 0000000..f07a526
--- /dev/null
+++ b/ReleaseNotes/release-notes-3.0.2.md
@@ -0,0 +1,35 @@
+# PLDroidMediaStreaming Release Notes for 3.0.2
+
+本次更新:
+
+## 版本
+
+- 发布 pldroid-media-streaming-3.0.2.jar
+- 更新 libpldroid_streaming_core.so
+
+## 功能
+
+- 新增摄像头抢占回调
+- 新增编码器异常状态回调
+
+## 优化
+
+- 优化录屏场景下可能出现的帧率较低的问题
+
+## 缺陷
+
+- 修复音视频和纯音频模式动态切换失败的问题
+- 修复个别机型推流画面变形的问题
+- 修复添加贴纸预览和播放效果不一致的问题
+- 修复软编场景实时刷新水印存在的闪烁问题
+- 修复特殊场景下偶现的 ANR 问题
+- 修复特殊场景下的崩溃问题
+
+## 注意事项
+
+- **从 v3.0.2 版本开始，请务必添加 `android.arch.lifecycle:extensions:x.y.z` 的依赖**
+- 从 v3.0.2 版本开始，`StreamingEnv.init(Context context)` 已被弃用，请更新到 `StreamingEnv.init(Context contex, String userId)` 进行环境的初始化，其中，userId 代表用户的唯一标识符，用于区分不同的用户
+- 从 v3.0.1 版本开始，Happy DNS 库请务必升级到 0.2.17 版本
+- **从 v3.0.0 版本开始，七牛直播推流 SDK 需要先获取授权才能使用。授权分为试用版和正式版，可通过 400-808-9176 转 2 号线联系七牛商务咨询，或者 [通过工单](https://support.qiniu.com/?ref=developer.qiniu.com) 联系七牛的技术支持。**
+- **v3.0.0 之前的版本不受影响，请继续放心使用。**
+- **老客户升级 v3.0.0 版本之前，请先联系七牛获取相应授权，以免发生鉴权不通过的现象。**
\ No newline at end of file
diff --git a/releases/arm64-v8a/libpldroid_streaming_core.so b/releases/arm64-v8a/libpldroid_streaming_core.so
index f36cfba..b880ee3 100755
Binary files a/releases/arm64-v8a/libpldroid_streaming_core.so and b/releases/arm64-v8a/libpldroid_streaming_core.so differ
diff --git a/releases/armeabi-v7a/libpldroid_streaming_core.so b/releases/armeabi-v7a/libpldroid_streaming_core.so
index 3c4f704..be2a2b8 100755
Binary files a/releases/armeabi-v7a/libpldroid_streaming_core.so and b/releases/armeabi-v7a/libpldroid_streaming_core.so differ
diff --git a/releases/armeabi/libpldroid_streaming_core.so b/releases/armeabi/libpldroid_streaming_core.so
index e285e32..703880c 100755
Binary files a/releases/armeabi/libpldroid_streaming_core.so and b/releases/armeabi/libpldroid_streaming_core.so differ
diff --git a/releases/pldroid-media-streaming-3.0.1.jar b/releases/pldroid-media-streaming-3.0.1.jar
deleted file mode 100644
index 8f94d3c..0000000
Binary files a/releases/pldroid-media-streaming-3.0.1.jar and /dev/null differ
diff --git a/releases/pldroid-media-streaming-3.0.2.jar b/releases/pldroid-media-streaming-3.0.2.jar
new file mode 100644
index 0000000..3a8f711
Binary files /dev/null and b/releases/pldroid-media-streaming-3.0.2.jar differ
diff --git a/releases/x86/libpldroid_streaming_core.so b/releases/x86/libpldroid_streaming_core.so
index bf7c271..3a1015c 100755
Binary files a/releases/x86/libpldroid_streaming_core.so and b/releases/x86/libpldroid_streaming_core.so differ