While other rumors have claimed that adding 3D imaging technology and OLED screens are hindering progress on the iPhone 8, Timothy Arcuri of Cowen and Company believes it’s the integrated fingerprint sensor that’s the main issue, AppleInsider reports. “For the 5.8-inch OLED version, the biggest bottleneck remains integrating an under-glass fingerprint sensor into the display — the current yield rate of Apple’s in-house AuthenTec solution remains low and AAPL seems unwilling to use other vendors’ products,” Arcuri wrote in a note to investors. Arcuri said Apple is faced with three options in the face of the problem: Ditch Touch ID in favor of facial recognition, move the fingerprint scanner to the back of the phone or delay production of the iPhone 8. He sees the first two options as pretty unlikely, expecting to see the iPhone 8 announced alongside new iPhone 7s and 7s Plus models but possibly becoming available for purchase later.