Mark Gurman of 9to5Mac has the exclusive report:
It appears that Apple is planning to build sapphire-crystal displays for future iPhones. This is opposed to this facility building sapphire components for future Apple Touch ID fingerprint readers and caps for camera sensors. The proof that GT Advanced is preparing to manufacture sapphire for displays comes from import/export records. As can be seen in the image above, GT Advanced has ordered Intego Sirius Sapphire Display Inspection Tool components.