From Black Friday through Christmas Day, one of the big mysteries of the mobile commerce business played out again, for all to see:

Apple users on iPhone and iPad accounted for five times what Google's Android users did when it comes to online shopping.

That phenomenon is bizarre when you consider that the vast majority — as many as 80% in some surveys — of all smartphone users are Android owners.

It doesn't make any sense.

Google's mobile users outnumber Apple's all over the place, but Apple users are the ones spending all the money. iOS users spent $93.94 per order, nearly twice that of Android users, who spent just $48.10.

What the heck is wrong with Android users?

Android people just seem to be sitting on their hands. Their phones are just as powerful as iPhones are. They have bigger screens, too. But they don't do anything with them. At least not financially.

We asked Google for comment. We'll update this post if the company gets back to us.

In the meantime, we turned to Simon Khalaf, CEO of Flurry, one of the larger mobile ad companies, to see if he had seen the same phenom in his business. He had a surprising answer for us: Androids are simply dumbphone replacement devices, and treated as such, he says. Despite the features at their fingertips, Android people use their phones for calling, texting and playing Bejeweled. They ain't shopping.

The Android cloud does have a silver lining. But before we get to that, it's worth hearing Khalaf out in full:

We have seen and published reports that an Android user is worth 1/4 of an iOS user, but that is based on virtual goods sales (mainly games). The IBM data seems to suggest that this is almost the same ratio for sales of physical goods (m-commerce).

I have done some anecdotal analysis on my own on some large specific e-commerce apps and found almost the same ratio of sales -- Basically one iOS user buys four times more than an Android user. But the analysis was on specific apps and not exhaustive, so we didn't say much.

As far as the main reason, we have theories -- but hard to validate. Main theory is that some Android devices are simply replacement of feature phones and not used as a smartphone, especially in the U.S. That big of a ratio is perplexing, but it is what it is. I don't have any reason to doubt IBM's data. Our data seems to be saying the same thing.

This is one reason why Apple isn't exactly panicking over the rise of Android in the East. Android users just aren't lucrative users for app developers, and app developers want to be in a media/commerce-rich environment, which right now is iPhone.

But there's a flip side to this: Imagine that the mobile business is an island, currently under development. Apple has essentially built a gleaming steel-and-glass tower on 20% of the mobile island that it owns. But Google owns the other 80%, and that land is undeveloped countryside. Who has the bigger opportunity in front of it? In the long-run, it's Google.

But in the short-run, it seems like the users on the majority of the island aren't interested in modern life.

Disclosure: The author owns Google stock.

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