Question: I am working on datasync service, i'm getting the json response from webserver. my question is how to pass that response to the activity from which i'm calling the service.

Answer: 
You can use EventBus and send the data to the desired Activity by Subscribing to the Event.

For Eg:

```
compile 'org.greenrobot:eventbus:3.0.0'

```

Eventbus Class 

```
public class DataSyn {
    public final List<YourModel> YourModel;

    public DataSyn(List<YourModel> YourModel) {
        this.YourModel = YourModel;
    }
}

```

Send Data from your response :

```
   EventBus.getDefault().post(new DataSyn(yourdataList));

Subscribe and Receive the Data wherever you need:

 @Override
 public void onStart() {
 super.onStart();
   EventBus.getDefault().register(this);
 }

@Override
public void onStop() {
    EventBus.getDefault().unregister(this);
    super.onStop();
}

@Subscribe(threadMode = ThreadMode.MAIN)
public void onDataRecevied(DataSyn event) {
    if (event.YourModel != null) {
        populateData(event.YourModel);
    }
}

```

Above is the most easiest way to share data
You can subscribe to a broadcast receiver in your activity with receiving a message, or you may look in push notification field...