Apple is set this week to have one of its classic big announcements, widely expected to be the launch of the next iPhone. The company, of course, is very tight-lipped about what it’s debuting and when. But it left a fairly big clue about what it’s planning on its invitation for this Wednesday, with the event date casting the shadow of a large “5” in the foreground.

Apple chief executive Tim Cook said this past spring that Apple would “double down” on secrecy surrounding new products, but that hasn’t stemmed the tide of rumors circulating about what’s in the new phone. Cobbling together information from leaks and other reports, the next iPhone seems likely to have a larger screen, LTE-capability, a thinner profile, a faster processor and no near-field communication reader. Many of these changes are expected to bring the iPhone in line with other smartphones on the market.

Screen size is a prime example of this. The screen of the iPhone has been the same for several generations, even as competitors have experimented with ever-larger screens of 5 inches or more that now test the limits of thumbs. As the Wall Street Journal and others have reported, Apple is all-but-expected to introduce a phone with at least a 4-inch screen.

Apple has had compelling reasons to keep the screen at 3.5-inches. One major strength of the iPhone is its extensive developer community, and the fewer versions of an app that developers have to deal with, the happier they are. And Apple is also a company that’s very focused on usable design, meaning that it’s unlikely to jump into offering a screen size that it doesn’t think will fit comfortably with the majority of consumers’ hands.

But the market has shown that users like slightly bigger screens on their phones now, particularly as video and browsing become a larger part of the connected life. So rumor has it that Apple, which reportedly has its eye on making its video offerings more accessible and comprehensive, will bump up its screen size and will incorporate new technology that gives customers the real estate of a bigger screen with little added heft.

Rumor also has it that the iPhone will be taller than its predecessors, which sounds like the way Apple has gotten around the fact that it’s simply a bit tough to use phones past a certain screen size for one-handed browsing. It’s the same approach Samsung took with the Galaxy S III, which has a tall but fairly slim 4.8-inch screen. (That’s made the phone much easier to use, though I’ve still found that it tends to overbalance when I go to tap the home button if I’ve got it in one hand.)

In the past, Apple has made it clear that it’s willing to adopt trends and technologies, but only in its own time. The company was a bit slower than others to get on the 3G bandwagon, saying that it didn’t feel the coverage was good enough. And the iPhone 4S still doesn’t support LTE, though the fact that the iPad does is a fairly good indication that Apple could incorporate the same technology into the iPhone.

Apple’s key advantage and disadvantage when it comes to timing on the market is that it only releases a new phone once per year. That means that the company can focus like a laser on making the best, most Apple-like phone it possibly can, while keeping an eye on the successes and failures of its competitors.

But it also means that it’s competing with companies that are trying to out-innovate the iPhone several times per year — meaning that there’s more pressure than ever to impress.

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