The Black Friday weekend is usually a great time for retail establishments and marketers. Through the four days after Thanksgiving in the U.S., stores hold sales and deep discounts to encourage consumer spending. With the rise in popularity of mobile devices like smartphones and tablets, these platforms are also increasingly becoming popular as e-commerce — or mobile commerce — platforms.

But while Android is on the rise nominally in terms of devices sold and in its market share, there seems to be a paradox at work. More and more people are buying Android smartphones and tablets. But the rate of engagement or online purchasing activity is not growing as fast.

Data from market analytics firm Asymco confirms this. Researcher Horace Dediu cites IBM Digital Analytics Benchmark's study that Black Friday sales rose 17.4%, while mobile access grew by 24% from the previous year.

But what's interesting to note is the dominance of iOS devices in access and online purchases. For instance, smartphones made up 54% of the mobile access, while tablets made up 46%. The iPad dominated tablet traffic at 88%, while Android devices made up the minority. Kindle and Nook devices took 5.5%, Galaxy Tab devices 1.8% and other devices 4%.

From the previous year's Black Friday, Android devices grew by a factor of 3.4, while iOS devices grew by 4.8. Interestingly, both the iPhone and iPad quickly overtook Android in terms of percentage of Black Friday online shopping activities.

The big question here is what is causing the disparity in behavior. “What is causing phone users to behave differently based on the devices they own?” asks Asymco, noting that the mobile market has grown more mature in the past year. What's clear with Android at this point is that “engagement is down as ownership is up.”

A few thoughts, based on the analysis:

• It can be expected that later adopters would engage less. Even as Android devices are selling like hotcakes, users who buy the devices a few years down the line are less likely to be more active in their online shopping.
• Price is not necessarily a factor. High-end devices like the Samsung Galaxy S3. “The most popular devices are not exactly cheap.”
• Engagement is not a frivolous platform attribute. This is causal to a platform's success because engagement leads to cash flows and economic activity (ad revenues, sales). This is particularly relevant to Android as a platform, given that device makers usually depend on more than monetizing hardware.
• It's not only shopping data that shows this kind of disparity in behavior between iOS and Android users. “[D]evelopers and publishers have been reporting distinct differences in consumption on iOS vs. Android.”
• There is something else at play in this “paradox” and it can involve several factors, including design considerations, user experience flaws or integration of e-commerce platforms.

Asymco's analysis did not say exactly what cause these differences. But the comment thread offers a few interesting insights into how the data could be interpreted. For example, there is question on how exactly Google counts Android activations. Do they double count a device when the device is updated? Another possible reason is the flood of “cheap, badly designed Android phones” that don't exactly make for a good web browsing or e-commerce experience.

I have a concern with the so-called Android engagement paradox, though. Amazon seems to have found success in its Kindle Fire lineup even if it is selling each device at a loss. They recoup the investment through sales of content and merchandise. Does the Black Friday data mean that device-makers who bank on content sales like Amazon are set to lose out in the long run?

As an Android user, how active are you in buying content and items using your smartphone or tablet?