Xteink X4 Pro review

I just bought an Xteink X4 Pro e-reader that snaps onto the back of my phone using MagSafe.

I’ve been trying to do more reading as of late, and I hoped that having a dedicated reading device would aid me in that venture. Well, I’m very glad to say that it has!

Here are some thoughts about the device.

#Hardware

• The touchscreen is responsive, with smooth scrolling support via swiping.
• The frontlight is superb, with granular control over the brightness and colour temperature.
• Battery life is indefatigable: the advantage of E Ink displays is that they only sip power when actively updating the page.
• The refresh rate is by no means instantaneous, but it’s fast enough that it’s not bothersome.
• The page turning buttons are accessible and easy to navigate with one hand.
• On-screen typography suffers a bit due to the lower screen resolution, but I didn’t experience any eye strain. I like to read on the smallest font size, and I still found it legible.
• The X4 Pro comes equipped with a replacable microSD card. I think it’d be pretty hard to fill up all the storage with books!
• It’s extremely lightweight, so you can hold it for hours on end without tiring.
• The lack of USB-C is my only gripe. It comes equipped with a (finicky) USB-C to pogo-pin adapter that provides both power and data transfer. It does the job, but it’s by no means ergonomic. And with all my other devices on USB-C now, it’s frustrating to have to keep around an adapter.

#Firmware

• The stock OS is … not great. But, thankfully, the device is unlocked and can be easily flashed using the browser via the Web Serial API. I’m using the superb CrossPoint firmware, and there’s a wonderful ecosystem of forks and plugins that have sprouted around it.
• The device runs on an ESP32, which is a wonderfully low-cost microcontroller. It’s pretty incredible that the firmware runs on just a few hundred kilobytes of RAM. I love these examples of constrained computing devices!
• Since the ESP32 has WiFi support, there’s a plethora of ways to transfer books: USB-C, local network, WiFi hotspot, and Calibre plugin. There’s even a way to connect it to Libby to borrow DRM-protected books from your library.
• There’s a lot to customise, if you so desire. I found the stock fonts to be a bit grainy, but I’ve been enjoying using Lexend Deca

As the old adage goes, the best book you have is the one you’re carrying. If it broke today, I’d probably go out and buy another one.

Update 19/10/2026: After travelling overseas on a long-haul the screen of my X4 Pro kicked the bucket. It worked and was protected throughout transit and there were no discernible scratches or marks on the body. However, the screen would no longer refresh and there were “fragmentation patterns” emanating from a spot. I can only assume that the e-ink screen itself is very fragile and susceptible to stress fractures. I contacted the support team and they kindly (and promptly!) shipped me a replacement device for free. Kudos to the Xteink team for the assistance, but lesson learned to be even more careful with it.