The last time Apple (NASDAQ: AAPL) updated the iPad Mini was back in September 2015. The upgrade to that tablet at the time was reasonable. Apple outfitted the new device -- the iPad Mini 4 -- with a brand-new liquid crystal display that offered superb color accuracy, good brightness, and reasonable contrast, according to testing performed by DisplayMate.

The tablet also enjoyed a reasonable improvement in internals, such as a move to the A8 processor, which was then one generation old.

Since then, Apple hasn't updated the product. In fact, the only update to the product line itself -- if you can even call it that -- is that Apple now offers the iPad Mini 4 in just a single storage configuration (128GB) at a relatively steep $399.

This leads to an interesting question: Is the iPad Mini product category dead?

We'll know soon

Apple introduced a new low-cost 9.7-inch iPad, marketed simply as iPad, back in March. This device seems to have resonated with consumers as iPad unit shipments surged in the quarter following its launch. I expect an updated version of this iPad -- with an identical form factor containing an A10 Fusion chip and possibly a new display with wide color support -- in the spring to try to keep the momentum in the iPad business going.

If Apple introduces this updated low-cost iPad with an upgraded iPad Mini, then that'd be the clearest sign that Apple plans to keep the product category going -- even if it won't be a category that gets a ton of attention from the company.

However, if the iPad Mini isn't updated at that time and the current iPad Mini 4 continues to be sold, perhaps at a reduced price, then I'd be willing to pronounce the iPad Mini category dead.

An even more obvious sign that the iPad Mini category is dead would be if Apple simply stopped selling the iPad Mini 4 altogether and didn't introduce a replacement.

Will Apple kill it?

I think the fate of the iPad Mini ultimately depends on how well the iPad Mini 4 continues to sell. Now, I know what you're thinking -- the iPad Mini 4 is now over two years old, so naturally it isn't going to be selling all that well. I agree.

What I think will matter to Apple is the trend in iPad Mini 4 sales. If iPad Mini 4 sales have continued to decline over the last two years, then that'd be a sign that potential iPad Mini customers are continuing to shift their dollars to other products, such as the larger-screen iPads or even to larger-screen phones.

However, if iPad Mini unit shipments have bottomed to some reasonably constant and significant level, then that would indicate that some customers are willing to buy the iPad Mini 4 even though it's rather dated. Apple might take that as a sign that there is intrinsic demand for the form factor itself and may view it as a worthwhile effort to update the internals of the iPad Mini to try to further boost sales.

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Ashraf Eassa has no position in any of the stocks mentioned. The Motley Fool owns shares of and recommends Apple. The Motley Fool has the following options: long January 2020 $150 calls on Apple and short January 2020 $155 calls on Apple. The Motley Fool has a disclosure policy.