Xteink S4 vs X4 & X4 Pro: Specs, Price, Status

The Xteink S4 is a pocket Android 11 e-reader reported on sale in China at CNY 339 (~$50), reportedly with a touchscreen and an adjustable front light, but as of August 2026 it has no international release planned. The two Xteink readers you can actually buy are the $69 button-only Xteink X4 and the $99 Xteink X4 Pro, which adds a front light and touchscreen without Android. This page compares the S4 against both, flags what’s reported versus disputed (including whether it’s actually shipping in China), and answers the price, availability, and firmware questions people keep asking.

S4 vs X4SpecsS4 vs X4 ProSame as X4 V2 Pro?PriceAvailabilityFirmwareRedditWait or Buy?FAQ

Xteink S4 vs X4: What’s the Difference?

The short answer, updated August 7, 2026

The core difference: the Xteink S4 runs full Android 11 with a touchscreen and front light, while the Xteink X4 runs proprietary ESP32-C3 firmware with physical buttons, no touch, and no light. The S4 is a reading-apps device (Kindle and Kobo via sideloading); the X4 is a distraction-free, hackable microcontroller reader that the CrossPoint community flashes with custom firmware. That split is why the comparison matters: they share a 4.3-inch pocket form factor but sit in completely different device classes.

The comparison also matters because the X4 broke out. Good e-Reader reported it as the first non-Kindle e-reader to reach Amazon’s e-reader top-10 (June 2026), and the S4 is Xteink’s Android-powered follow-up aimed at readers who want Kindle and a backlight rather than a microcontroller to hack.

The figures in the S4 column below come from press coverage of the on-sale China unit (Good e-Reader, Notebookcheck), not our own hands-on testing. The X4 column is from the official xteink.com listing.

A few notes on the X4 side, since earlier drafts of this post got them wrong:

• The X4 is a microcontroller, not a “32 GB storage device.” It runs on an ESP32-C3 with a microSD slot for your library. There is no “32 GB internal storage” and no 32 GB-to-16 GB downgrade; that was a fabricated claim and it’s gone. The S4’s 32 GB is a real number for a different, Android-based device, not the X4.
• “Xteink backlight” is the X4’s most-searched missing feature. The base X4 has no front light at all. If a backlight is your deal-breaker and you want a shipping device, the X4 Pro already has one; the S4 remains China-only.
• X4 RAM is only about 380 KB of usable SRAM. That tiny budget is exactly why stock firmware sticks to DRM-free EPUB and TXT, and why the firmware community exists.

For the row-by-row three-way breakdown, including the X4 Pro, see the full X4 vs S4 vs X4 Pro comparison.

Xteink S4 Specs (Reported China Unit)

Reported Xteink S4 specs: a 4.3-inch E-Ink touchscreen, Android 11, 2 GB RAM, 32 GB storage, an adjustable front light, a 1,400 mAh battery, USB-C, and a 95 g body, priced at CNY 339 ($50) in China. Every figure comes from tech press covering the China retail listing (Good e-Reader, Notebookcheck), not hands-on testing. What’s left open is mostly international-market detail and the exact chip.

So when you see “2 GB RAM” or “1,400 mAh” quoted around the web, those trace to press coverage of the China retail listing. What no longer holds up is the “on sale and heading overseas” framing that surrounded those reports in May.

Xteink S4 vs X4 Pro: Which Should You Buy?

Buy the shipping Xteink X4 Pro unless you specifically need Android reading apps. The X4 Pro delivers the two features people wait for the S4 to get, an adjustable front light and a touchscreen, on a device you can order internationally today. The S4’s only real edge is Android (Kindle, Kobo, and Libby as native apps by sideloading), and getting one means importing from China.

Here is the head-to-head:

• OS: The X4 Pro runs Xteink’s own XTOS (the same non-Android family as the X4 and X3). The S4 runs Android 11 (reported), so it can sideload Kindle, Kobo, and Libby as apps; XTOS cannot.
• Front light and touch: Both add them. The X4 Pro has a confirmed adjustable warm/cool (dual-tone) front light and a touchscreen; the S4 reportedly has an adjustable front light and touch too.
• Availability: The X4 Pro launched July 21, 2026 at $99 ($109 list) with a first batch of 500 units and ships internationally now. The S4 is China-only with no international release planned.
• Charging trade-off: The X4 Pro drops USB-C for a pogo-pin connector and drops the bottom button row (side buttons stay). The S4 reportedly keeps USB-C.
• Firmware: Neither runs CrossPoint today. CrossPoint is ESP32 firmware and does not run on the Android S4; it does not run on the X4 Pro yet either, though Lowcock references an official XTEINK/CrossPoint partnership that could bring a port later.

Full X4 Pro specs, what’s in the box, and upgrade advice live in our X4 Pro guide.

Buy the X4 Pro · $99 at xteink.com  or read the full X4 vs S4 vs X4 Pro comparison first.

Is the Xteink S4 the Same as the X4 V2 Pro?

No. The Xteink S4 and the X4 V2 Pro are two different devices. The device the community called the “X4 V2 Pro” launched as the Xteink X4 Pro on July 21, 2026 at $99, runs Xteink’s non-Android XTOS, and ships internationally. The S4 runs Android and is China-only with no international release planned. They are easy to confuse because both add a front light and a touchscreen over the base X4, but only the X4 Pro keeps the flashable XTOS architecture, and only the S4 runs Android apps.

If you searched “xteink s4 v2” expecting one product, you were looking at two: the shipping X4 Pro (buy it today) and the S4 (import-only). See the X4 vs S4 vs X4 Pro comparison for the full breakdown.

Xteink S4 Price: How Much Does It Cost?

The Xteink S4 is reported on sale in China at CNY 339 (~$50); there is no international price because no international release is planned. That China figure comes from Good e-Reader and Notebookcheck coverage of the domestic retail listing. A ~$70 international figure circulated in May 2026 press coverage, but it was always an estimate, and it is moot now that Joshua Lowcock’s tracker reports no plan to sell the S4 outside China.

For a device you can actually price and buy today, the base Xteink X4 is $69 and the Xteink X4 Pro is $99 ($109 list). Both ship internationally; the S4 does not.

When Will the Xteink S4 Be Available?

There is currently no international release date for the Xteink S4, and there may never be one. Joshua Lowcock’s S4 tracker reports that Xteink has no current plans to release the S4 internationally (on Amazon or through official channels), citing his China supply-chain sources and the S4’s absence from any FCC database. If that holds, importing from China is the only route. Even the China launch is murkier than it first looked: Good e-Reader and Notebookcheck reported the S4 on sale domestically, but Lowcock reports the April pre-orders never shipped and the expected July China ship window slipped during compliance testing.

The S4 first surfaced through Xteink’s own channels in mid-April 2026: an official teaser video and a Note.com blog post titled “A Sneak Peek at the New Generation Android-Powered Pocket E Ink Reader,” followed by a price-announcement YouTube Short. Press coverage from Notebookcheck, Good e-Reader, and eReadersForum followed. Here is the sourced sequence that matters:

For live release-status tracking across all Xteink devices, see our devices hub.

Will CrossPoint or Custom Firmware Run on the S4?

No. CrossPoint and every fork target the ESP32-C3 in the X3 and X4; the Android-based Xteink S4 is a different platform. CrossPoint, CrossInk, and Microreader, plus the smaller forks (AvesO3 for AO3 fanfiction, SUMI the offline-first X4 build, INX for X3 button-mapping) all run on the X3/X4 microcontroller. None run on the S4. If your reason for buying Xteink is flashing a custom build, the S4 is not your device; an unlocked X4 is.

The flip side is that the S4’s Android base sidesteps the ESP32 ceiling entirely. Where the X4’s ~380 KB of usable SRAM limits stock firmware to DRM-free EPUB and TXT (the whole reason the CrossPoint scene exists), the S4 can sideload ordinary reading apps: Kindle, Kobo, Libby, Moon+ Reader, ReadEra, or KOReader’s Android build. Press coverage points to no Google Play Store, so apps get sideloaded directly.

One caution for X3/X4 buyers: in early May 2026, Liliputing reported that Xteink began blocking custom firmware on units bought from AliExpress, Taobao, and other Chinese domestic retailers, while stating that units from xteink.com or Amazon are unaffected. If custom firmware matters to you, buy from xteink.com or Amazon and run the USB flasher on arrival. Our locked vs unlocked buying guide ranks sellers by risk and walks through the arrival-day test.

We do not yet have a review unit, though the S4 has now launched in China. This section will be updated once we can test KOReader behaviour, refresh rate, and Kindle rendering firsthand.

What Does Reddit Say About the Xteink S4?

Reddit’s consensus on the Xteink S4 is “interesting, but buy the shipping X4 instead.” The r/ereader community keeps recommending the X4 to newcomers, with the usual caveat that the missing front light and app limitation are real trade-offs. On r/xteinkereader, the S4 and X4 V2 Pro delayed-launch thread captures the mood: enthusiasm for Android, frustration at the slipping timeline.

The reason the S4 draws interest at all is the same reason people buy any tiny Xteink: it pulls you off your phone.

An Android reader that runs Kindle and adds a backlight lowers that friction even further. The risk, as commenters note, is that putting full Android on the device drags the phone’s distractions back in. Whether the S4 stays a calm reading tool or becomes another glowing rectangle of notifications is the question only a shipping unit can answer.

Where the X3 Fits

If you’re new to the brand, the X4 isn’t the only shipping Xteink: there’s also the smaller X3. The X4 has the larger 4.3-inch screen; the X3 is more compact, charges over a magnetic pogo-pin cable (no USB-C port), and adds NFC. The X3-vs-X4 decision is the most common question in the community, and a device you can buy today usually beats one that’s only on sale in China. Our X3 vs X4 comparison walks through screen size, charging, and firmware support in detail.

One firmware caveat if you lean X3: its pogo cable comes in two pinouts. A 4-pin cable carries power and data; a 2-pin cable charges only. With a 2-pin cable the laptop flasher never sees the device, and people routinely misread that as “my unit is locked.” Check the cable before you conclude anything about firmware.

Should You Wait for the S4 or Buy an X4 Today?

The honest answer depends on one question: are you here to read, or here to tinker? Here’s how to decide without overthinking it.

If you land in the “buy now” column, here’s the practical move:

Steps:

1. Decide screen size first (larger 4.3-inch X4 or the smaller X3) using the X3 vs X4 guide.
2. Buy from xteink.com or Amazon, not a grey-market reseller, so the firmware isn’t locked.
3. Run the USB flasher on arrival to confirm the unit is unlockable; if you’re on an X3, make sure you have a 4-pin pogo cable, not a 2-pin charge-only one.
4. Read for a week first. Load a few DRM-free EPUBs, transfer them, and read before deciding whether you even want custom firmware.

Buy the base X4 · $69 at xteink.com  or step up to the X4 Pro at $99 for a front light and touch.

If you land in the “wait” column, be clear-eyed: there is no official international listing, no FCC filing, and no plan for one. Don’t pre-order through a grey-market reseller to jump a line that may never form. Treat any future official international listing plus first independent reviews as the signal to act.

FAQ

Open questions a review unit will need to answer: battery life in real use (Android burns far more power than the ESP32, so a bigger cell mostly offsets overhead rather than extending read time); E-Ink refresh on Android (poorly tuned drivers feel laggy and ghosty, the biggest unknown for day-to-day feel); KOReader and Kindle rendering on this specific panel; and whether the bootloader is unlockable at all.

Where to Follow S4 Updates

• Official Xteink: product page will update if pre-orders open internationally; Xteink Note blog for official announcements
• Joshua Lowcock’s tracker: most detailed third-party tracker, updated when news breaks
• Good e-Reader: consistent Xteink coverage
• eReadersForum: community threads including the S4 Android pivot discussion
• r/ereader: community discussion; search “Xteink S4” for the latest threads
• This blog: hands-on coverage will appear here when a unit is available

Last updated: August 7, 2026. Status: Joshua Lowcock's tracker reports no international S4 release is planned (no FCC filing), and China fulfillment is disputed (press reported it on sale; Lowcock reports April pre-orders unshipped). This page compares the S4 against the shipping $69 X4 and $99 X4 Pro, and updates when the S4's status changes in either direction. Sources: Official teaser, Xteink Note, Notebookcheck, Good e-Reader, Joshua Lowcock, Liliputing.