Is there a better way to check if an OUI is being used by a mobile phone or a router? e.g. There are plenty of huawei/apple routers and if one of them is in your neighborhood, you'd always get incorrect count. Similarly, there are many infamous smart phones and people use them but your code seems to ignore them.
I had been downloading the zone file for .PK domains on daily bases until they blocked the zone transfers. Based on comparison of these daily zone files I managed to publish the statistics [1] and also broke the news about hacked .PK domains [2] which was picked up by all leading tech blogs and news agencies.
Currently, I cannot find a way to get the zone file even by officially requesting the registry manager.