MageWorx's Others Also Bought Magento extension
Others Also Bought Magento extension replaces native Magento Related Products block with the one which displays most relevant products based on the order history of your customers. This technique is being used on all famous e-commerce websites such as Apple Store. You can set the number of Also Bought Products to display and sort them either by popularity or randomly. However, if there are not enough products to display, pre-defined Related Products will be added to the list.