The World's Smallest E-Reader Just Got A Genuinely Necessary Upgrade

There's a specific kind of product that goes viral for being charming before it's actually good. Xteink's original tiny e-readers were exactly that: small enough to magnetize to the back of your phone, small enough to disappear into a pocket, small enough that the whole appeal was basically "look how tiny this is." Book lovers on social media ate it up.

The problem was the actual reading experience. Button-based navigation. No front light. No touchscreen. It was the kind of device you bought because the idea of it was irresistible, then quietly kept as a backup to your Kindle because using it day to day was genuinely clunky.

Xteink apparently heard that complaint loud and clear, because the X4 Pro exists specifically to fix it.

What Actually Changed

The X4 Pro adds two things people had been asking for since the original X3 and X4: a touchscreen and a front light. That's it. That's the whole pitch. But those two additions are the difference between "a fun gadget you show people" and "a device you could realistically use as your primary e-reader."

Physically, not much else moved. The X4 Pro weighs 72 grams and measures just 5.95 mm thin, essentially identical in size to the standard X4. So Xteink didn't sacrifice the thing that made these devices go viral in the first place (their absurd, pocketable smallness) to add the features people wanted. That's a genuinely smart trade-off.

Why The Front Light Actually Matters

This is where the review gets personal, and honestly, it's the most convincing part of the whole story. The reviewer's nightly routine involves reading in the dark before falling asleep, lights off, reading until drowsy enough to close the Kindle and go to sleep. With the X4 Pro's added front light, that routine shifted almost entirely to the new device during the review period.

Using the front light on its dimmest setting (still slightly brighter than ideal for bedtime, with a warm color temperature), the X4 Pro became the go-to bedside device. That's a real behavioral shift, not just a spec-sheet improvement. A front light isn't a nice-to-have for an e-reader that's marketed as an everyday companion; it's the feature that determines whether you can actually use the thing after sunset without a lamp.

There's an interesting tension buried in the review too: reading on the X4 Pro before bed apparently feels a bit like the old bad habit of scrolling on a phone in bed; you hold it closer to your face than you would a Kindle, given the smaller screen. That's worth sitting with for a second. It's not necessarily a bad thing (falling asleep after e-ink is still far easier than after a backlit phone screen), but it's a real trade-off of going this small. You gain pocketability; you lose a bit of the "let it rest on the mattress at arm's length" reading posture bigger e-readers allow.

Page-turning flexibility got a genuine upgrade too; you can now tap the side of the screen or use the physical side buttons, giving you more options for how you actually hold the device while reading.

Where It Falls Short (And Where It Doesn't)

Not every change was purely positive. The X4 Pro switched from USB-C charging (used on the original X4) to a magnetic pogo charger. Since e-ink devices need charging so infrequently, that's not a dealbreaker for most people but if you're someone who cares specifically about USB-C universality across your gadgets, it's a legitimate ding.

Battery life remains genuinely excellent, which is basically the standard for e-ink devices at this point but still worth confirming: three weeks of near-daily use and still sitting at 60% battery. The added front light does drain it somewhat faster than the light-free predecessors, but the difference is apparently barely noticeable in practice.

Software got a real update too, and notably Xteink didn't lock down the ability to load open source code, which matters to the kind of enthusiast crowd that got excited about these devices in the first place. Getting content onto the device via Wi-Fi and Bluetooth works, but remains a bit clunky; pulling the microSD card and using the included microSD to USB adapter to transfer files directly from a computer is apparently the more reliable method.

The Library Book Problem

Here's the catch that's worth knowing before you buy: you're not getting library e-books on this thing. Xteink doesn't integrate with apps like Libby, and even if you technically borrow an e-book from your library, you can't load it onto the X4 Pro library e-books use protected .epub files specifically designed to prevent that kind of transfer.

Buying an .epub directly from a publisher, though? No problem, loads right on. Just don't expect Amazon purchases to work here Amazon's ecosystem is a walled garden, meaning books you buy through Amazon are locked to Amazon devices only, regardless of the fact that you paid for them. That's an Amazon policy frustration more than an Xteink one, but it's relevant if your book-buying habits run through Kindle purchases.

Who This Is Actually For

At $99, available currently only through Xteink's own website, the X4 Pro sits in an interesting spot. It's not trying to replace a full-size Kindle or Kobo for someone doing serious, sustained reading the reviewer specifically noted going back to a standard Kindle for something like re-reading the Odyssey, since a 4.26-inch screen makes poetry with deliberate line breaks genuinely annoying to read.

But for the use case it's actually built around a pocketable, always-with-you device that nudges you toward reading a few pages instead of scrolling Instagram in a checkout line, or a genuinely comfortable bedtime reading companion- the addition of a touchscreen and front light moves the X4 Pro from "adorable novelty" to "device I'd actually recommend using regularly." That's a meaningful jump for a $99 gadget, and it suggests Xteink is actually listening to the community that made these tiny e-readers go viral in the first place.