This video allegedly shows the inside of a Chinese click farm where they provide fake ratings for apps. Apparently if you want to create and write fake app reviews you cannot spoof a device; you actually need to have a physical device with an IMEI number and a MSISDN number. So now you can buy a bunch of good reviews for yourself or a bunch of negative reviews for your competitors.
So now you should question some of those really badly written reviews you see.
The original video can be viewed here.