3 Smartphone-Sized E-Readers That Are Perfect For On-The-Go Reading

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Reading books on a train or bus might sound whimsical and fun in theory, but it can be quite a hassle in practice. In the name of convenience, you'd probably rather read on your phone than lug around a full-size book. After all, your phone fits in one hand, can easily be slipped into your pocket, and isn't as heavy as a physical book. 

But there are a few reasons why reading on an e-reader beats reading on your smartphone, and one of the biggest is eye strain. Staring at your device for long hours can be pretty exhausting for your eyes, especially with the screen at full brightness. The problem is, most favored e-readers like the Kindle and Kobo aren't exactly as portable as a phone. They're almost as big as a tablet and can be awkward to hold in one hand without using a grip. As a middle-ground solution, you can go with a smartphone-sized e-reader with the same e-ink screen as the Kindle, like these devices.  

Measuring 6.3" x 3.1" x 0.31" and weighing just 6oz, the Boox Palma 2 looks and feels like any other smartphone. It uses a Carta 1200 e-paper display with a resolution of 300 PPI. And like a Kindle, this display is also equipped with a dual-tone front light, letting you change both the brightness and warmth to your liking. While the Palma 2 uses e-paper, it still responds pretty well to touches, thanks to the Boox Super Refresh technology. This makes the screen feel smoother and more smartphone-like than a Kindle's.

When it comes to reading, the Palma 2's reading interface is just as minimal as any other e-readers'. It includes standard elements like the pages, battery life, and time and familiar Kindle tools like highlight, translate, and text customizations. If you're a fan of audiobooks, the Palma 2 is built with Bluetooth and its own speaker for convenience. The device's battery life, on the other hand, is reported to last for about a week or two, depending on how much you read a day. 

Aside from being an e-reader, the Boox Palma 2 functions like a smartphone. It runs Android 13 and is powered by an octa-core processor, with 6 GB of RAM and 128GB of storage, which can be expanded via a microSD card. Since it's an Android phone, it comes with the Play Store installed. That means you can download all sorts of apps, from social media apps like TikTok to productivity apps like Gmail. Another notable smartphone-like feature of the Palma 2 is the 16MP rear camera with an LED flash, which is especially useful for scanning documents. 

The Xteink X4 is the very definition of a portable e-reader for on-the-go reading. It's only 4.49" × 2.72" × 0.23" in size and 2.6oz in weight, making it even smaller and lighter than your typical smartphone. It easily fits in your pocket, but you can also attach it to your phone using the magnetic back or wear it on your wrist with a lanyard looped through the built-in lanyard hole.

Hardware-wise, the X4 comes with a 220 PPI e-ink screen that can be used in either portrait or landscape mode. It doesn't include a front light or touchscreen feature, though. It does have Dark Mode, so you can still read comfortably in low-light environments. For navigation, the X4 still uses physical buttons. Moving to storage and battery, its storage isn't built in, unlike the Kindle. You get a 32GB microSD card in the box instead, which is easily upgradable to 512GB. Its battery has a capacity of 650mAh, so if you read for one to three hours a day, expect the e-reader to last up to 14 days. The X4 works with both EPUB and TXT files and supports font customization using your own BIN font files.

Featuring a 6.13" Kaleido 3 color e-ink screen, the Viwoods AiPaper Reader C is one of the coolest e-ink gadgets you can buy on Amazon, and for good reason. It's especially made for manga and comic book readers, but also for textbook readers who prefer a pop of color over monochrome displays. In addition to color, the e-ink offers 150 PPI resolution and a cold and warm front light that you can manually adjust to suit your needs.

If you normally read colored books, you can easily leave the AiPaper Reader C's default settings as is. But there's actually a Grayscale Mode you can enable to turn the screen black-and-white for better focus. It's one of the e-reader's four refresh modes, along with Best Display Mode (sets contrast to max), Fast Mode (has smooth but quick page turns), and Quick Refresh Mode (clears ghosting automatically).

Like a smartphone, the AiPaper Reader C runs on 4GB of RAM and 128GB of storage. It has a 2,580mAh battery that should last you at least a few days if you mainly use the device for reading. Because the e-reader is powered by Android 16, you can install pretty much any third-party app of your choice.

What really makes the AiPaper Reader C stand out is its built-in AI. You can activate it via the side button and use it to get content summaries, ask questions about the author, and basically anything in between. It lets you use models from ChatGPT, Google Gemini, DeepSeek, and Qwen. All these features are packed in a smartphone-sized form factor — around 6.28" x 3.16" x 0.26" — but still super light at 4.9oz.