In a Branch chat, which at the time of this writing is still going on, Daring Fireball's John Gruber says, according to what he's heard, iOS 7 is running behind schedule and that it will bring a significant user interface (UI) refresh.
What I've heard: iOS 7 is running behind, and engineers have been pulled from OS X 10.9 to work on it. (Let me know if you've heard this song before.)
Gruber went on to say that he's heard that iOS 7 is a "significant system-wide UI overhaul" and the iOS engineers who are allowed to carry around devices with iOS 7 on them even have special privacy filters on their devices which reduces viewing angles. This is to prevent others from accidentally getting a glimpse of the new iOS design.
Back in 2007, Apple delayed the release of OS X Leopard to concentrate work on iPhone. Gruber hints that this could be the case with Mac OS X 10.9 and iOS 7.
iMore's Rene Ritchie follows up Gruber's comments, saying that he's heard that Ive's work with iOS 7 is "making many people really happy, but will also apparently make rich-texture-loving designers sad."
His comments come during a Branch talk that includes Gruber, Ritchie, TechCrunch's MG Siegler, Engadget's Tim Stevens, The Next Web's Matthew Panzarino and more.
Ritchie follows up his earlier predictions, noting that he's heard that an event for a new, 9.7-inch iPad is or was planned for April, but it was contingent upon the new iPad being ready for release. He also notes that he's hearing the iPhone 5S will arrive in August, although Ritchie also says it could be a July/August window rather than a specific month.
As for what could be on the iPhone 5S, both Siegler and Panzarino say they've heard a lot about biometrics on the new device. The feature would apparently be used for payments and identification. Panzarino notes it wouldn't be surprising to see AuthenTec's biometric technology in Apple devices so soon after Apple purchased the company last July because of the urgency of the deal.
Finally, Siegler says he's heard "a whisper" that Apple's Passbook team is due for a shakeup and is in "shambles," though Ritchie points out that Forstall's departure could be the reason for the Passbook team's troubles.
