diff --git a/libs/hbb_common/protos/message.proto b/libs/hbb_common/protos/message.proto
index 433e186d5..2f732539c 100644
--- a/libs/hbb_common/protos/message.proto
+++ b/libs/hbb_common/protos/message.proto
@@ -122,13 +122,13 @@ message TouchEvent {
   oneof union {
     TouchScaleUpdate scale_update = 1;
   }
-  repeated ControlKey modifiers = 2;
 }
 
 message PointerDeviceEvent {
   oneof union {
     TouchEvent touch_event = 1;
   }
+  repeated ControlKey modifiers = 2;
 }
 
 message MouseEvent {
diff --git a/src/client.rs b/src/client.rs
index 798bc83f2..ccdae0512 100644
--- a/src/client.rs
+++ b/src/client.rs
@@ -1967,8 +1967,8 @@ pub fn send_mouse(
 }
 
 #[inline]
-pub fn send_touch(
-    mut evt: TouchEvent,
+pub fn send_pointer_device_event(
+    mut evt: PointerDeviceEvent,
     alt: bool,
     ctrl: bool,
     shift: bool,
@@ -1995,10 +1995,7 @@ pub fn send_touch(
         mouse_event.x *= factor;
         mouse_event.y *= factor;
     }
-    msg_out.set_pointer_device_event(PointerDeviceEvent {
-        union: Some(pointer_device_event::Union::TouchEvent(evt)),
-        ..Default::default()
-    });
+    msg_out.set_pointer_device_event(evt);
     interface.send(Data::Message(msg_out));
 }
 
diff --git a/src/ui_session_interface.rs b/src/ui_session_interface.rs
index 033033faf..a88a02edb 100644
--- a/src/ui_session_interface.rs
+++ b/src/ui_session_interface.rs
@@ -35,8 +35,8 @@ use hbb_common::{
 use crate::client::io_loop::Remote;
 use crate::client::{
     check_if_retry, handle_hash, handle_login_error, handle_login_from_ui, handle_test_delay,
-    input_os_password, load_config, send_mouse, send_touch, start_video_audio_threads, FileManager,
-    Key, LoginConfigHandler, QualityStatus, KEY_MAP,
+    input_os_password, load_config, send_mouse, send_pointer_device_event,
+    start_video_audio_threads, FileManager, Key, LoginConfigHandler, QualityStatus, KEY_MAP,
 };
 #[cfg(not(any(target_os = "android", target_os = "ios")))]
 use crate::common::GrabState;
@@ -695,11 +695,11 @@ impl<T: InvokeUiSession> Session<T> {
             scale,
             ..Default::default()
         };
-        let evt = TouchEvent {
-            union: Some(touch_event::Union::ScaleUpdate(scale_evt)),
-            ..Default::default()
-        };
-        send_touch(evt, alt, ctrl, shift, command, self);
+        let mut touch_evt = TouchEvent::new();
+        touch_evt.set_scale_update(scale_evt);
+        let mut evt = PointerDeviceEvent::new();
+        evt.set_touch_event(touch_evt);
+        send_pointer_device_event(evt, alt, ctrl, shift, command, self);
     }
 
     pub fn send_mouse(