diff --git a/app/src/main/java/org/autojs/autojs/pluginclient/DevPluginService.java b/app/src/main/java/org/autojs/autojs/pluginclient/DevPluginService.java
index c0638c2d..a5609c9e 100644
--- a/app/src/main/java/org/autojs/autojs/pluginclient/DevPluginService.java
+++ b/app/src/main/java/org/autojs/autojs/pluginclient/DevPluginService.java
@@ -2,17 +2,27 @@ package org.autojs.autojs.pluginclient;
 
 import android.annotation.SuppressLint;
 import android.os.Build;
+import android.os.Handler;
+import android.os.Looper;
+import android.support.annotation.AnyThread;
+import android.support.annotation.MainThread;
+import android.support.annotation.WorkerThread;
+import android.util.Log;
 import android.util.Pair;
 
+import com.google.gson.JsonElement;
 import com.google.gson.JsonObject;
+import com.stardust.util.MapEntries;
 
+import org.autojs.autojs.BuildConfig;
 import org.autojs.autojs.tool.EmptyObservers;
 
 import java.io.IOException;
 import java.net.Socket;
+import java.net.SocketTimeoutException;
+import java.util.Map;
 
 import io.reactivex.Observable;
-import io.reactivex.Observer;
 import io.reactivex.android.schedulers.AndroidSchedulers;
 import io.reactivex.schedulers.Schedulers;
 import io.reactivex.subjects.PublishSubject;
@@ -23,6 +33,11 @@ import io.reactivex.subjects.PublishSubject;
 
 public class DevPluginService {
 
+    private static final int CLIENT_VERSION = 2;
+    private static final String LOG_TAG = "DevPluginService";
+    private static final String TYPE_HELLO = "hello";
+    private static final long HANDSHAKE_TIMEOUT = 10 * 1000;
+
     public static class State {
 
         public static final int DISCONNECTED = 0;
@@ -53,26 +68,33 @@ public class DevPluginService {
     private static final int PORT = 9317;
     private static DevPluginService sInstance = new DevPluginService();
     private final PublishSubject<State> mConnectionState = PublishSubject.create();
+    private final DevPluginResponseHandler mResponseHandler = new DevPluginResponseHandler();
+    private final Handler mHandshakeTimeoutHandler = new Handler(Looper.getMainLooper());
+
     private volatile JsonSocket mSocket;
 
     public static DevPluginService getInstance() {
         return sInstance;
     }
 
+    @AnyThread
     public boolean isConnected() {
         return mSocket != null && !mSocket.isClosed();
     }
 
+    @AnyThread
     public boolean isDisconnected() {
         return mSocket == null || mSocket.isClosed();
     }
 
+    @AnyThread
     public void disconnectIfNeeded() {
         if (isDisconnected())
             return;
         disconnect();
     }
 
+    @AnyThread
     public void disconnect() {
         mSocket.close();
         mSocket = null;
@@ -82,6 +104,7 @@ public class DevPluginService {
         return mConnectionState;
     }
 
+    @AnyThread
     public Observable<JsonSocket> connectToServer(String host) {
         int port = PORT;
         String ip = host;
@@ -91,36 +114,80 @@ public class DevPluginService {
             ip = host.substring(0, i);
         }
         mConnectionState.onNext(new State(State.CONNECTING));
-        return createSocket(ip, port)
+        return socket(ip, port)
                 .observeOn(AndroidSchedulers.mainThread())
-                .doOnNext(socket -> {
-                    mSocket = socket;
-                    mConnectionState.onNext(new State(State.CONNECTED));
-                })
-                .doOnError(e -> {
-                    mConnectionState.onNext(new State(State.DISCONNECTED));
-                    e.printStackTrace();
-                });
+                .doOnError(this::onSocketError);
     }
 
-    private Observable<JsonSocket> createSocket(String ip, int port) {
+    @AnyThread
+    private Observable<JsonSocket> socket(String ip, int port) {
         return Observable.fromCallable(() -> {
-            JsonSocket jsonSocket = new JsonSocket(new Socket(ip, port));
-            DevPluginResponseHandler handler = new DevPluginResponseHandler();
-            jsonSocket.data()
+            JsonSocket socket = new JsonSocket(new Socket(ip, port));
+            socket.data()
                     .observeOn(AndroidSchedulers.mainThread())
                     .doOnComplete(() -> mConnectionState.onNext(new State(State.DISCONNECTED)))
-                    .subscribe(data -> handler.handle(data.getAsJsonObject()), e -> {
-                        e.printStackTrace();
-                        mConnectionState.onNext(new State(State.DISCONNECTED));
-                    });
-
-            writePair(jsonSocket, "device_name", new Pair<>("device_name", Build.BRAND + " " + Build.MODEL));
-            return jsonSocket;
+                    .subscribe(data -> onSocketData(socket, data), this::onSocketError);
+            sayHelloToServer(socket);
+            return socket;
         })
                 .subscribeOn(Schedulers.io());
     }
 
+    @MainThread
+    private void onSocketError(Throwable e) {
+        e.printStackTrace();
+        if (mSocket != null) {
+            mConnectionState.onNext(new State(State.DISCONNECTED, e));
+            mSocket.close();
+            mSocket = null;
+        }
+    }
+
+    @MainThread
+    private void onSocketData(JsonSocket jsonSocket, JsonElement element) {
+        if (!element.isJsonObject()) {
+            Log.w(LOG_TAG, "onSocketData: not json object: " + element);
+            return;
+        }
+        JsonObject obj = element.getAsJsonObject();
+        JsonElement type = obj.get("type");
+        if (type != null && type.isJsonPrimitive() && type.getAsString().equals(TYPE_HELLO)) {
+            onServerHello(jsonSocket, obj);
+            return;
+        }
+        mResponseHandler.handle(obj);
+    }
+
+    @WorkerThread
+    private void sayHelloToServer(JsonSocket socket) throws IOException {
+        writeMap(socket, TYPE_HELLO, new MapEntries<String, Object>()
+                .entry("device_name", Build.BRAND + " " + Build.MODEL)
+                .entry("client_version", CLIENT_VERSION)
+                .entry("app_version", BuildConfig.VERSION_NAME)
+                .entry("app_version_code", BuildConfig.VERSION_CODE)
+                .map());
+        mHandshakeTimeoutHandler.postDelayed(() -> {
+            if (mSocket != socket && !socket.isClosed()) {
+                onHandshakeTimeout(socket);
+            }
+        }, HANDSHAKE_TIMEOUT);
+    }
+
+    @MainThread
+    private void onHandshakeTimeout(JsonSocket socket) {
+        Log.i(LOG_TAG, "onHandshakeTimeout");
+        mConnectionState.onNext(new State(State.DISCONNECTED, new SocketTimeoutException("handshake timeout")));
+        socket.close();
+    }
+
+    @MainThread
+    private void onServerHello(JsonSocket jsonSocket, JsonObject message) {
+        Log.i(LOG_TAG, "onServerHello: " + message);
+        mSocket = jsonSocket;
+        mConnectionState.onNext(new State(State.CONNECTED));
+    }
+
+    @WorkerThread
     private static int write(JsonSocket socket, String type, JsonObject data) throws IOException {
         JsonObject json = new JsonObject();
         json.addProperty("type", type);
@@ -128,14 +195,38 @@ public class DevPluginService {
         return socket.write(json);
     }
 
+    @WorkerThread
     private static int writePair(JsonSocket socket, String type, Pair<String, String> pair) throws IOException {
         JsonObject data = new JsonObject();
         data.addProperty(pair.first, pair.second);
         return write(socket, type, data);
     }
 
+    @WorkerThread
+    private static int writeMap(JsonSocket socket, String type, Map<String, ?> map) throws IOException {
+        JsonObject data = new JsonObject();
+        for (Map.Entry<String, ?> entry : map.entrySet()) {
+            Object value = entry.getValue();
+            if (value instanceof String) {
+                data.addProperty(entry.getKey(), (String) value);
+            } else if (value instanceof Character) {
+                data.addProperty(entry.getKey(), (Character) value);
+            } else if (value instanceof Number) {
+                data.addProperty(entry.getKey(), (Number) value);
+            } else if (value instanceof Boolean) {
+                data.addProperty(entry.getKey(), (Boolean) value);
+            } else if (value instanceof JsonElement) {
+                data.add(entry.getKey(), (JsonElement) value);
+            } else {
+                throw new IllegalArgumentException("cannot put value " + value + " into json");
+            }
+        }
+        return write(socket, type, data);
+    }
+
 
     @SuppressLint("CheckResult")
+    @AnyThread
     public void log(String log) {
         if (!isConnected())
             return;