What to expect from Apple's iPhone event

While there's still no official confirmation of what Apple plans to show off Tuesday, it's the worst kept secret in tech: we're getting new iPhones.

Apple (AAPL, Fortune 500) keeps its lips pretty tight when it comes to future products. But Apple does have to rely on other companies to help make the iPhone, which means leaks are inevitable.

We may not know everything about the new iPhone, but we have a pretty decent idea of what to expect.

As usual, Apple will update its flagship iPhone model, which is expected to be called the iPhone 5S. It's not likely to be a radical redesign, but Apple still might have a few new things to brag about.

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For starters, the iPhone 5S is expected to come in a gold - or champagne, depending on who you talk to - color. The first hint of this came from a leaked factory image of an iPhone part, and then another, and another. AllThingsD eventually found trusted sources to confirm the rumor.It's also possible the 5S will come in a lighter shade of grey, providing a fourth option for iPhone buyers.The iPhone is also expected to have upgraded hardware, which should come as no surprise. Many believe the iPhone 5S will feature Apple's A7 processor, a dual-core chip promising31% more computing power.

According to other leaks, the iPhone 5S will have an improved camera and an upgraded,dual-LED flash to make your night shots look less washed out.