I am a self-confessed lover of E Ink devices. Whether it’s an e-reader, writing tablet, or minimalist mobile phone, I am always keen to check out new gadgets that use the power efficient screen technology made famous by the Amazon Kindle.

The latest E Ink curio to hit the internet is called the Xteink X4, a remarkably small e-reader just 5.9mm thick with a 4.3-inch screen, meaning you can finally have a Kindle alternative that can slip into a shirt pocket – all for the equivalent of about £50.

The X4 costs $69 and weighs just 74g, and even has a magnetic back, with Xteink claiming you can attach the whole device to the back of an iPhone using MagSafe. But as The Verge discovered, it’s not guaranteed to work on any iPhone as they are all different sizes.

Xteink looks like it knows this, so it ships the X4 with adhesive magnetic rings in the box so you can attach the e-reader to any phone or phone case – or wherever you want it to sit.

Unlike a Kindle or Kobo, e-readers with screens large enough to mimic the rough size of the page of a physical paperback, the Xteink X4 is small enough to grip edge-to-edge with one hand. It’s even dinkier than the Boox Palma 2 and Palma 2 Pro I’ve tested, which are designed to look and feel like tall-screen smartphones.

The X4 is notable as it sits in its own design category, perhaps most similar to the size of an iPhone 4 or 5 from more than a decade ago, but thinner with power button on the side and page turn buttons on the side and bottom edge.

With a USB-C charging port and even a hole to thread a lanyard loop through, the X4 is sold as a pocketable Kindle rival – but thanks to its software, it could end up being more of a hindrance to easy reading than initial impressions suggest.

Kindle and Kobo are easy to use because they have dedicated book stores, hosted by the companies. Say what you will about monopolisation of e-books, but in terms of user friendliness, these devices win because all you have to do is search for the book you want on your device, and then you can buy it.

In the UK, I prefer Kobo because you can use the OverDrive service to link your library card, and then borrow library books for free on your device. In the US, you can also do this on a Kindle.

It’s nearly as easy on the Boox Palma devices because they run Android. This means you can install the Kindle or Kobo companion apps and access your purchases that way. Android also lets you click and drag EPUB files and other e-book file formats over from your PC onto the device to view and read.

The X4 does not run Android. To get books onto it, Xteink recommends transferring e-books onto a microSD card on your PC or Mac, and then putting the card into the X4. This already requires a certain level of niche knowledge about e-books and software, especially as Kindle and Kobo files won’t necessarily work on the X4 as they could have restrictive digital rights management (DRM) attached.

The X4 will only read EPUB or TXT files. You can download e-books for free from legal websites such as Project Gutenberg, which has more than 75,000 titles that are no longer covered by copyright – so you can stock up on old classics. We’re talking Frankenstein, Moby Dick, Pride and Prejudice and Crime and Punishment.

That could limit you to centuries-old novels unless you buy e-books from sources other than the Kindle store. You might also not love the screen specs, as the display has a 220 pixels per inch resolution, which means text appears a little less sharp than the 300ppi you can expect from the latest Kindle or Kobo.

Add to that the fact the screen has no backlight, and you might want to give the X4 a miss.

But if you are a tech tinkerer who likes unique tech that doesn’t break the bank, Xteink is currently selling the X4 for $69 plus shipping. If you want to experiment with a new form factor and don’t want to fork out for a premium Kindle, this could be the gadget for you.