diff --git a/doc/gamepad.md b/doc/gamepad.md
index f78fb828..607bb935 100644
--- a/doc/gamepad.md
+++ b/doc/gamepad.md
@@ -28,6 +28,8 @@ scrcpy --gamepad=uhid
 scrcpy -G  # short version
 ```
 
+Note: UHID may not work on old Android versions due to permission errors.
+
 
 ### AOA
 
diff --git a/doc/mouse.md b/doc/mouse.md
index ec4aea63..ae7c6834 100644
--- a/doc/mouse.md
+++ b/doc/mouse.md
@@ -53,6 +53,8 @@ scrcpy --mouse=uhid
 scrcpy -M  # short version
 ```
 
+Note: UHID may not work on old Android versions due to permission errors.
+
 
 ### AOA