Apple is expected to unveil the latest iPhone at a major press event at 10 a.m. PT (1 p.m. ET) on Tuesday. Because it is very unlikely that the company will unveil a new device that doesn't operate on the recently announced iOS 7 operating system, this will likely be when the plastic wraps are taken off and people will learn when their iPhone will sport the new John Ive inspired design.

Many have speculated that people will be able to download the new iOS as early as tomorrow. However, that doesn't necessarily mesh with the way Apple has unveiled new operating systems in the past, according to this rundown courtesy of GottaBeMobile,

• iOS 3 release two days before the iPhone 3GS
• iOS 4 release three days before the iPhone 4
• iOS 5 release two days before the iPhone 4S
• iOS 6 release two days before the iPhone 5

If Apple sticks to this system, the new iOS will be out either the Sept. 17 or 18. The iPhone will be unveiled tomorrow. Pre order sales are expected for Sept. 13. This puts the release date of the iPhone 5S on Sept. 20.

One other school of thought on the matter is that, since this is such a revolutionary redesign to the iOS that people have come to know and love, they might want to put it as close to the iPhone 5S release as possible. The iOS 7 could cannibalize the iPhone 5S' sales. The new iOS will make an iPhone 4S seem like an entirely new device. While that's going to be fun for users, the company likely doesn't want to push a software update that makes an old phone feel new when it is trying to sell something that actually is.

The event kicks off Tuesday at Apple's Cupertino Calif. headquarters.