Anthony if you use the regular "onClick" event on buttons, they won't be triggered. You can try in one of my demo scenes "Perspective_And_TopDown_Demo" rotate the camera and release your click on top of one of the top right buttons.
chanon IsInputMatching return true, even I touch on the UI. Is it possible to set it to return false when I touch on the UI?
Anthony Sorry for the response delay. IsInputMatching() is not meant for that but you can use this method to check if the pointer is over a UI element if( EventSystem.current != null && EventSystem.current.IsPointerOverGameObject() ) Hope that helps!