Boox Picco vs Xteink X4: Which Pocket E-Reader to Buy

This is part of our Boox hub. For the Picco on its own, see what the Boox Picco is and is not; for the whole small-reader field, including the 6-inch Kindle and Kobo, see our best small e-reader roundup.

The matchup

What the Boox Picco vs Xteink question really is

Until this autumn, a reader smaller than a phone meant an Xteink. The Chinese brand’s X3 and X4 are card-sized e-ink readers that snap to the back of a phone, and they had the category to themselves. Then Boox listed the Picco, a 3.97-inch reader at 58 grams, and the Boox Picco vs Xteink question appeared in search within days. It is a fair question, because the two brands are making the same bet: a reader you carry like a bank card, with no bookstore and no Android, that reads the files you send it.

One thing to settle before any spec: on 19 October 2026 the Picco was a pre-order, and Boox’s store said it would ship around November. Xteink’s three readers were in stock, with the X4 Pro shipping in one to five days and the X3 in one to two business days. Nobody outside Boox has used a Picco yet, so this comparison reads both companies’ own product pages against each other, says where a page is silent, and will be revisited once Piccos are in hands.

The lineup

The four readers, side by side

Here is the whole field. Prices are each store’s US price on 19 October 2026; Xteink’s X4 Classic price includes a free base stand, and its X4 Pro was listed as a sale against a $129 regular price.

Two of the four are not really the Picco’s rivals. The X4 Classic and the X3 have no front light and no touchscreen; they are daylight readers turned with buttons, and their prices reflect that. The reader the Picco is priced against is the X4 Pro, which adds both, and the gap between them is $10.99. That is the pair the rest of this comparison keeps coming back to.

Read those two cards as a trade. The X4 Pro gives you a third of an inch more screen, about 20 percent more battery and $11 back, and it is on a shelf. The Picco gives you a published resolution, a two-tone light, a USB-C port instead of a magnetic pin, and a file-transfer app from a company that has shipped e-ink devices for years. Xteink’s X4 Pro page lists the Pro’s size, battery, weight, light and storage but no pixel density or dimensions, so where this page says “not published”, that is what the store says, not a gap in our reading.

Screen

Screen, light and touch

All four are monochrome e-ink panels. The Picco’s is 3.97 inches at 480 by 800 pixels, which Boox prints as 235 ppi, and Boox says it anti-aliases text on that small panel so letters stay clean. The X4 Classic is a 4.3-inch panel at 219 ppi: a bigger page with slightly coarser pixels. The X3 is the sharpest of the set at 259 ppi, on the smallest screen at 3.7 inches. The X4 Pro shares the Classic’s 4.3-inch size, and Xteink does not print its density. Every reader here is a step below the sharpness a full-size 6-inch reader holds; what you buy instead is a page that fits in the same pocket as your keys.

Lighting is where the field splits. The Picco has a dual-tone front light with adjustable brightness and colour temperature, warm to cold, plus a dark mode that flips to white text on black, and a physical function switch you can set to toggle either. The X4 Pro has a front light too; Xteink’s comparison strip lists it simply as yes, and the Pro’s page does not state whether the tone is adjustable. The X4 Classic and X3 have no light at all. Xteink’s own FAQ says so and points buyers who read in bed to a clip-on light it sells, or to the X4 Pro.

If you would not read without a light, the choice is two readers, not four.Screen, light and touch

Touch follows the same line. The Picco and the X4 Pro have capacitive touchscreens and physical page buttons, so you can tap or press. The X4 Classic and X3 are buttons only, with page-turn keys on both edges, and both offer a motion page turn where a shake or tilt flips the page. A screen you cannot touch never turns a page by accident in a pocket, which is a real argument for the button-only models; it is just not one the Picco offers. The Picco also rotates four ways, so it reads in landscape or flipped for a left hand.

Formats

Formats and getting books on: BOOX Tiles against XT-Cloud

Neither brand’s page names a bookstore, an Android version or an app store for these readers. Both are readers for files you already own, and the question is which files and how they get there. This is the section where the Picco pulls ahead on paper.

Boox lists sixteen document formats for the Picco: EPUB, MOBI, AZW3, AZW, AZW5, FB2 and its zipped forms, FB3, FBZ, TXT, PDB, PRC, RTF, HTML, XHTML, HTM and CHM, plus PNG, JPEG, WEBP, BMP and GIF images. PDF is not on the list, which matters for anyone hoping to read papers on it; our Picco explainer goes into that. Files reach the Picco through the BOOX Tiles app on a phone, the booxtiles.com website, or a USB cable via the same site, and the phone and web routes work over shared Wi-Fi or through the cloud when you are elsewhere. The Tiles app also carries a Pomodoro timer, a to-do list and a countdown that show on the reader.

Xteink’s spec sheets are narrower: EPUB and TXT as documents, BMP (and JPG on the X3) as images, and custom fonts. Its FAQ widens that to MOBI and PDF with a caveat that the firmware may not fully support them, so it recommends converting both through the official Xteink app before transfer, and it has its own XTCH, XTC and XTCZ formats for image-heavy files such as comics. Transfer is by the app, which Xteink calls XT-Cloud, or by the microSD card; the X4 Pro adds USB. XT-Cloud is free, and Xteink says plainly that it may introduce paid features later. The X3’s page adds one more line worth reading twice: it works with the official app only, no third-party apps. If your library is EPUBs from Calibre or a DRM-free store, either brand reads it. If it is a mix of MOBI, AZW3 and FB2 files, the Picco opens them as they are and the Xteink wants them converted first.

Body

Size, weight, battery and the back of your phone

Boox puts the Picco at 105.5 by 62 by 5.5 mm and about 58 grams, which is the size of a playing card and the weight of the Xteink X3 to the gram. The X3 is shorter and a hair thinner at 97.6 by 63.7 by 5.1 mm. The X4 Classic is the biggest body here, 114 by 69 mm, and the thinnest at 4.9 mm, for 68 grams; the X4 Pro is 72 grams at the same screen size. None of these weighs as much as a phone case. The practical difference is the X4’s extra height, which is the price of its 4.3-inch page.

Batteries: the Picco and the X4 Classic both carry 920 mAh cells, the X4 Pro 1,100 mAh, the X3 650 mAh. Boox prints no battery-life estimate for the Picco, and Xteink prints one only for the X3, which it rates at 10 to 14 days on a charge at one to three hours of reading a day. Charging is a real point of difference. The Picco has a USB-C port and a microSD slot, with a 16 GB card in the box and support up to 2 TB. Every Xteink charges through magnetic pogo pins; the X4 Classic ships with a magnetic charging adapter, the X3 with a pogo-pin cable and a card reader. Xteink’s cards go to 256 GB. Storage on all four is the microSD card; none of the pages lists internal memory.

The phone-back trick is Xteink’s signature. Every Xteink has a magnetic backplate, and the X4 V2, which is the current X4 Classic, has the ring built in so it snaps to the back of an iPhone; Xteink notes it protrudes a little and sits flattest on Pro Max models. Boox gets the Picco there with its $12.99 magnetic case, which has the ring in the case rather than the reader. The X4 Classic also has a second small e-ink panel on its back that shows the cover of the book you are reading or a photo of your choice; the Picco’s equivalent is a custom screensaver on the main screen. The X3 has one feature nobody else here has: NFC that can simulate an unencrypted access card, with Xteink’s own warning that it is for your own badges and nothing else.

Price

Price, stock, warranty and the box

The Picco is $109.99 in the US store and $99.99 in Boox’s Hong Kong store, both pre-orders shipping around November, with a one-year warranty, a pre-installed 16 GB microSD card, three screen protectors and a quick-start guide in the standard box. Boox has been quiet about an exact date; it first said October and moved to November, so treat the month as approximate. Boox’s next reader up is the $199.99 Go 6 Gen II, which runs Android, so the Picco is the cheapest Boox by $90 and the only one without an app store; our best Boox e-reader guide places it in that range.

Xteink’s prices on 19 October 2026 were $79 for the X4 Classic, with a free base stand in every variant and the magnetic charging adapter, a matte screen protector, two adhesive metal rings and a 16 GB card in the box; $99 for the X4 Pro in Space Black, shown as 23 percent off a $129 regular price, or $109 with a base stand; and $69 for the X3, or $84.99 with a stand and adapter. All three were in stock. Xteink’s store gives a one-year warranty, a 30-day return window and free shipping on orders over $79, which means a $69 X3 on its own can carry a shipping charge and the $79 Classic sits right on the line. One caution that applies to both brands: neither warranty covers damage from unofficial firmware, and Xteink says so in as many words on every product page.

Where that leaves the money: a Picco in its case is $122.98 on pre-order; an X4 Pro with a stand is $109, today. For a reader that stays in a pocket rather than on a desk, the stand is optional and the Picco’s case is close to mandatory if you want it on your phone, so the honest like-for-like is $122.98 against $99, a $24 gap in Xteink’s favour. If you also write on a bigger Boox, the Boox templates we make for the Note Air and Go 10.3 are not for a reader this size, and nothing on this page should be read as a reason to buy one; the Picco and the Xteinks are for reading, full stop.

Verdict

Verdict: Boox Picco or Xteink X4

The people who can turn this from a spec-sheet read into a real one are the ones who own an Xteink today and have a Picco on order. If that is you, tell us in the comments how the two lights compare at night, whether the Picco’s touchscreen turns pages by accident in a pocket, and how long each one actually lasts between charges, and we will fold it into this Boox Picco vs Xteink comparison and the rest of our Boox guides. If you went one way and regretted it, that is worth knowing too.

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