diff --git a/AUTHORS b/AUTHORS
index 64488bfc62..e314db297a 100644
--- a/AUTHORS
+++ b/AUTHORS
@@ -80,6 +80,7 @@ Paul Kapustin <pkapustin@gmail.com>
 Peng Yu <yupeng323@gmail.com>
 Philipp Hancke <philipp.hancke@googlemail.com>
 Piasy Xu <xz4215@gmail.com>
+Qi Luo <aidenluo.me@gmail.com>
 Rafael Lopez Diez <rafalopezdiez@gmail.com>
 Ralph Giles <giles@ghostscript.com>
 Raman Budny <budnyjj@gmail.com>
diff --git a/examples/objc/AppRTCMobile/ARDAppClient.m b/examples/objc/AppRTCMobile/ARDAppClient.m
index ccd5bb0662..9d5107d33b 100644
--- a/examples/objc/AppRTCMobile/ARDAppClient.m
+++ b/examples/objc/AppRTCMobile/ARDAppClient.m
@@ -212,7 +212,11 @@ static int const kKbpsMultiplier = 1000;
     return;
   }
   _state = state;
-  [_delegate appClient:self didChangeState:_state];
+  __weak ARDAppClient *weakSelf = self;
+  dispatch_async(dispatch_get_main_queue(), ^{
+    ARDAppClient *strongSelf = weakSelf;
+    [strongSelf.delegate appClient:strongSelf didChangeState:strongSelf.state];
+  });
 }
 
 - (void)connectToRoomWithId:(NSString *)roomId