As bottlenecks in making components for the iPad mini with Retina have gradually been removed, Apple has increase orders in November to nearly four million units, according to Taiwan-based supply chain makers.

　　Currently, Apple's orders for the iPad mini with Retina have already surpassed those for the first-generation iPad mini, the sources noted.

　　As for the iPad Air, because the supply chain had a longer preparation time, the device is seeing much more stable supply compared to previous-generation devices when launched, the sources said.

　　Shortages of Retina displays were the main reason causing the iPad mini to suffer from tight supply since manufacturing a 7-inch Retina display is more difficult than a 9.7-inch one, the sources explained.

　　Because of the issue, the iPad mini with Retina did not become available in retail channels until mid-November.