Barnes & Noble’s new Nook Glowlight Plus (yes, there is a new one!) has the same high-resolution display as the Kindle Paperwhite. Its battery lasts just as long. It weighs a little less, it costs a little more. Both hold more books than you could ever read. On paper, they’re fairly similar. In the tub or at the beach, they’re a world apart.

That’s because the new Nook Glowlight Plus is water-resistant. Specifically, it’s IP67 certified, which means that it should be able to survive up to 30 minutes of fresh water submersion down to a meter. It’s also not the first waterproof flagship ereader; that distinction goes to Kobo’s Aura H20, released last fall, which received the same certification.

Waterproofing may not be enough to convince you to buy a Glowlight Plus; that depends on where you read, how clumsy you are, and how the device actually performs. There’s no downside to it, though. It’s a built-in, invisible layer protection, whether you ever actually use it or not. To the extent that there’s an ereader arms race, water-resistance is the heaviest artillery since built-in front-lighting. A feature which, incidentally, Barnes & Noble beat Amazon to as well, with 2012’s Simple Touch with GlowLight.

“As we were thinking about continuing the same offering to our customer base, part of the process has been to reach out to the customers,” says Barnes & Noble Chief Digital Officer Fred Argir. “Customers have given us great feedback; they said they want a waterproof device.”

And not just Nook customers. There’s enough demand for water-resistant Kindles that you can pay $100 to WaterFi, or a company like it, Paperwhite, for hydrophobic aftermarket embellishments. It’s not just ereaders either; we’re at a point where even the iPhone is more waterproof than a Kindle.

BARNES & NOBLE

Amazon declined to comment on if and when a waterproof Kindle might be coming, but it doesn’t seem likely to arrive any time soon. The Paperwhite just got a refresh in June. There are rumors of an update to the high-end Voyage coming in November, but they aren’t substantiated, and even if they were, they don’t include water-resistance. Hopes for a more durable Kindle may be sunk, at least until next year.

That gives the Nook Glowlight Plus an important window as the most affordable water-resistant ereader, one that doesn’t sacrifice pixel density or design to achieve those ends.

How long that window remains open depends as much on Amazon’s response as it does the ereader industry generally. Last year, Forrester Research projected sales to fall to 7 million per year by 2017, a significant drop from the 25 million sold in 2012. That’s partly because ereaders are durable; a Kindle or Nook you bought three years ago likely works perfectly well today. But it’s also because tablets and large smartphones are obviating the need for a dedicated reading device at all. Not to mention that, as The New York Times notes, physical books are back into fashion.

Both Amazon and Barnes & Noble sell tablets and physical books in addition to ereaders; they’ll still be able to sling content, to varying degrees of success, regardless of platform. But while the ereader market may be shrinking, it still serves millions of people. It’s a category that deserves, and needs, innovation. Barnes & Noble waited two years after the previous Glowlight to deliver just that. Here's hoping it won’t take Amazon as long to respond in kind.