With the share of smartphone-toting Americans approaching the two-thirds mark, owning an iPhone isn't quite the status symbol it used to be. But as Apple's flagship mobile device continues its march around the globe, it's becoming clear that the price of an iPhone varies dramatically depending on where you live.

From the folks at Mobile Unlocked comes an interactive feature that plots the price of Apple's 16GB iPhone 5S as consumers see it from their home countries. Using a mix of quotes from the online Apple Store and local wireless carriers, Mobile Unlocked looked at both the absolute price of an iPhone as well as the price in relation to a country's per-capita GDP. The idea, says Mobile Unlocked's Darren Kingman, was to riff off another popular measure of currency alignment.

"We've altered it slightly to be a modern version of the Big Mac Index by the Economist, focusing on the iPhone instead," says Kingman.

The Big Mac Index, if you need a refresher, attempts to highlight how much more or less residents of other countries are paying for what should in theory be the same price for the same commodity all around the world. This works really well for McDonald's burgers, given how readily accessible they are. It gives a hint of what currencies may be overvalued or undervalued .

But the work of the Mobile Unlocked team also tells something about where iPhones are or are not affordable relative to peoples' incomes.

The most expensive place in the world to buy an iPhone is Jordan, where a single phone goes for $940 before taxes. Income levels in Jordan help ease the pain, though.

The place where iPhones are most expensive relative to incomes isn't China, despite many reports on how the iPhone 5C is still too expensive for the average Chinese citizen. Rather, India is the winner for the least affordable place to buy an iPhone. There, even though an iPhone retails for $759 before taxes, it accounts for more than 22 percent of India's per-capita GDP.

In the United States, by comparison, a basic iPhone 5S costs $649 before taxes and accounts for just 1.37 percent of the country's per-capita GDP. With the average global price of an iPhone at about $795 before taxes, this makes the United States (unsurprisingly) the cheapest place in the world to buy an iPhone.