CCDevice.patch

--- CCDevice.mm	(revision 6)
+++ CCDevice.mm	(working copy)
@@ -102,11 +102,12 @@
 
 - (void)accelerometer:(CMAccelerometerData *)accelerometerData
 {
-    _acceleration->x = accelerometerData.acceleration.x;
-    _acceleration->y = accelerometerData.acceleration.y;
-    _acceleration->z = accelerometerData.acceleration.z;
-    _acceleration->timestamp = accelerometerData.timestamp;
-    
+#warning Get current data as opposite to the one from the queue. Its an ugly hack and needs to be replaced!
+    _acceleration->x = _motionManager.accelerometerData.acceleration.x;
+    _acceleration->y = _motionManager.accelerometerData.acceleration.y;
+    _acceleration->z = _motionManager.accelerometerData.acceleration.z;
+    _acceleration->timestamp = _motionManager.accelerometerData.timestamp;
+
     double tmp = _acceleration->x;
     
     switch ([[UIApplication sharedApplication] statusBarOrientation])

The laggy issue that this fixes has existed since cocos2d-x 3.0 and currently exists in 3.5.
I hope that this or an alternative fix makes it into 3.6, since the laggyness/slowness is so significant that it seems to build up and make the accelerometer take up to 10 seconds to respond on iOS after running for about 30 seconds.

Thanks for posting this fix!