E-book readers: A buyer's guide

With the launch of Amazon's recent 2017 Kindle Oasis, e-reader prices have hit a new high: the 32GB wi-fi-and-3G version of the new Oasis costs a princely £319.99 (or $349.99 in the US). But you don't have to spend anywhere near that much on an e-reader -- there's plenty of choice.

Here are the key factors to look for in an e-reader, followed by a comparison of current devices from the leading vendors in the UK: Amazon and Kobo.

Device size

Device size matters on a couple of fronts: portability and usability. Some e-readers are small enough to drop into a reasonably-sized pocket. Others will more likely need to go into a bag. Smaller devices are much easier to hold and use one-handed, which will matter if you like to read while standing on crowded commuter transport.

It's also worth remembering that both Kobo and Kindle e-readers benefit from mobile apps that have access to your entire library, will synchronise to the last place read, and can be used on Android and iOS devices (tablets and phones), so you don't have to carry the e-reader itself for your current read to be available.

Screen size

Screen sizes vary between six inches and 7.8 inches, and it's worth considering what will work best for you. If you like large text, then a bigger screen will mean less time spent moving between pages -- although, obviously, a bigger screen also means a bigger, heavier device.

Screen quality

The more pixels in an e-reader's screen, the more readable it is. But I've been using e-readers since their very earliest days, have used all those in the comparison chart that's part of this article, and have found them all perfectly readable. Having said that, the 300ppi (pixels per inch) of the very latest devices do provide the best reading experience.

There's more to readability than pixel density, though. For example, all of the e-readers compared here let you change font and font size, so it's possible to get the text just right for your eyesight and personal preferences.

Screen light

Screen lights weren't around on early e-readers, and their introduction was a real boon. They allow you to read at night without having a separate light nearby, and that boosts the range of circumstances in which you can read, as well as allowing you to read in bed without disturbing your partner. For me, a light is essential. On older e-readers the light setting needs to be made manually, but modern devices support automatic adjustment. If you're concerned about reducing blue light when reading at night, some e-readers will do this (see the comparison chart below).

Page turning

All the e-readers in the comparison chart use a touchscreen, and some also have navigation buttons. Working out which page-turning method you prefer is crucial as it's the most frequent operation you'll carry out. Check reviews to see how impressed reviewers are with the speed of screen refreshes too: there's little more irritating than waiting a millisecond longer than is comfortable for the display to refresh.

Connectivity

Some people manage perfectly well with just wi-fi, but I prefer to have mobile broadband connectivity as well. That means I can buy books or replenish an e-reader from my purchase library when I'm out and about, and there's no real need to stock up before I go away for a few days.

Storage capacity

Storage capacity varies on e-readers, and most don't have external storage support so you're stuck with what's on the device. This isn't likely to be an issue unless you want to take advantage of the very latest Kindle feature -- audiobook support, because audio requires much more storage capacity than text. If you're happy with text alone, then 4GB of storage will hold about 3,000 books. Importantly, all of the books you've bought are stored in the cloud, so they don't all need to be on your device at the same time.

Waterproofing

Waterproofing is relatively rare in e-readers. If you think you'll need it -- because, say, you're prone to dropping tech in the bath -- then be sure to check for that feature.

Battery life

E-reader battery life is measured in weeks rather than hours, thanks to their low-power screen technology. There's no trend yet for fast-charging in e-readers, and it can take a while to administer a full charge to a reader. If you need to eke out battery life, turn off wi-fi and 3G when you don't need them.

E-Reader specs and prices (UK)

Related coverage

Kobo Aura H2O 2017, First Take: A waterproof e-reader that's easy on the eyes

Kobo's latest e-reader offers waterproofing and automatic blue-light exposure control, but misses a trick by omitting public library lending support.

Amazon Kindle Oasis: E-reader for the one percent

At nearly $300 to start, Amazon's flagship ebook reader device is no bargain. But that isn't why it exists. This is how $30 e-readers are made. Rich people and early adopters take the price hit for the rest of us.

Amazon unveils waterproof Kindle Oasis with built in Audible support

The device marks the 10-year anniversary of the Amazon's original Kindle e-reader launch.

Read more

• 2017 Amazon Kindle Oasis review: Better than paper and waterproof too
• Amazon Kindle 2016, First Take: Affordable, but backlight-free
• Amazon Kindle Voyage: Great screen, but pricey for an e-reader
• Kobo Aura H2O 2017, First Take: A waterproof e-reader that's easy on the eyes
• Kobo Aura ONE, First Take: Large-screen e-reader with 8GB of storage
• Best E-Book Readers for 2018 (CNET)