deviceMotionEvent.js

var SHAKE_THRESHOLD = xxx;  
    var last_update = 0;  
    var x, y, z, last_x, last_y, last_z;  
       
    function deviceMotionHandler(eventData) {  
      var acceleration =eventData.accelerationIncludingGravity;  
       
      var curTime = newDate().getTime();  
       
      if ((curTime - lastUpdate)> 100) {  
       
          var diffTime = curTime -last_update;  
          last_update = curTime;  
       
          x = acceleration.x;  
          y = acceleration.y;  
          z = acceleration.z;  
       
          var speed = Math.abs(x +y + z - last_x - last_y - last_z) / diffTime * 10000;  
           
               if (speed > SHAKE_THRESHOLD) {  
                                alert("shaked!");  
          }  
          last_x = x;  
          last_y = y;  
          last_z = z;  
        }  
    }