This is Apple's revenue by product. Wait until you see profit... Last month, I noted that the 5-year-old iPhone is already the most profitable product in the world.

The iPhone, I estimated, is so profitable that it generates more profit than just about any other company on earth, not just product.

The iPhone generates more profit than GE, for example (all of GE). It generates more profit than Microsoft. It generates more profit than Google and Walmart. It generates almost as much profit as Exxon-Mobil!

Well, it turns out I was too conservative.

The iPhone is likely even more profitable than I thought!

In fact, new information suggests that the iPhone is so profitable that it is responsible for the vast majority of Apple's profits.

Last week, in a lawsuit with Samsung, Apple was released documents that showed the relative gross profit margin for its iPhones and iPads.

This information allows us to estimate, to an extent never before possible, just how much profit Apple derives from the iPhone.

The bottom line?

The iPhone likely accounts for almost two-thirds of Apple's profits.

The iPad, meanwhile, likely accounts for almost a relatively paltry 10%-15% of Apple total profit--less than most people probably think. Macs, iPods, Apple TVs, and other Apple products, meanwhile, likely account for about 30%.

I'll walk through the estimates below, but here are the key points and implications:

The iPhone will likely generate more than $30 billion of operating profit for Apple this year

Apple's bottom line is much more dependent on the iPhone than most people realize

The iPad contributes much less to Apple's profit than most people realize (It's a much less profitable product)

If the iPhone stumbles, or if Apple becomes "an iPad company," the company's profit margin will get walloped

The increasing price pressure and lengthening upgrade cycles in the smartphone and tablet markets increase the risk that Apple's overall profit margins will soon begin to decline

The iPhone 5 is an absolutely critical product for the company: If it's a blowout hit, Apple's earnings will soar; if it's a dud, Apple's earnings will disappoint