For one thing, the iPhone 6 Plus cannot adequately replace the iPad mini (and certainly not the iPad Air) for those who want a tablet as a productivity device. In most such situations, a larger display is almost a prerequisite. Such users also typically want a device that can work well with a physical keyboard. The iPhone 6 Plus does not fill the bill here.
And don't forget that a slight decline in sales is not the same thing as low sales. As Tim Cook pointed out: "In the last 12 months, Apple sold 68 million iPads." That's nothing to sneeze at.
Finally, it's difficult to argue that Apple's decision not to update the iPad mini was due to the success of the iPhone 6 Plus — considering that the new iPhone was not even for sale at the time Apple made its decision. I suppose you could say Apple was being prescient. But Apple presumably had high expectations for the iPhone 5C; things don't always go as Apple expects. Still, Apple's decision does suggest that it currently sees a stronger future for the larger iPad. Consistent with this, rumors continue to swirl that Apple will expand the iPad in a still larger direction next year — with a 12-inch "iPad Pro/Plus."
So where do we go from here? I see two trends emerging.
First, there will be an increasing split among smaller and larger iOS tablet devices. The iPad mini and the iPhone Plus will be the options for those preferring a smaller device — while the iPad Air and presumably an iPad Pro/Plus will be the choices for those who find greater value in a larger size tablet. There will be less movement back and forth, and less overlap of features, between these two categories.
Second, there will be a rebalancing of the mobile computing market. Those who predicted that tablets would eradicate laptops, or that mini-sized tablets would eradicate larger ones, were hasty in their judgments. Instead, as users become more familiar with the pros and cons of each category, a significant number of tablet users are gravitating back to a laptop. Tablet sales may continue to decline for a period of time. However, once the market stabilizes, I expect tablet sales to start a slower but significant upward trajectory again.
For many users and circumstances, the iPad remains the best choice among all of Apple's devices. This will not change for the foreseeable future. In the mobile market, there's room enough for iPads, iPhones, and MacBooks to all be successful. That's what you'll see in the months ahead. And in the end, as Tim Cook indicated at the most recent earnings call, Apple doesn't really care what device you wind up buying, as long as the Apple logo is on it.
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