While the Apple Watch has ensured that smartwatches create the most buzz in the wearable tech space, smart jewellery is quietly building up a solid following by offering a more fashionable and discreet alternative for women.
Due to their small size, smart rings are tricky get right. We've trawled the world of wearables to seek out the most interesting smart rings - the good, the bad and the very, very ugly…
NFC Ring 2016
The second gen NFC ring, crowdfunded on Kickstarter, can be used to unlock doors and smartphones, transfer information and link people.
The ring packs two NFC tag inlays - one for public information and one for more sensitive stuff. The private tag - for things such as your door lock and payment information - sits on the inner part of the ring closest to the palm, so that it requires a deliberate gesture to use. The public portion, for stuff you want to give out, like your email address, sits on the top side of your finger.
Waterproof to 50m, the ring comes in a range of subtle designs including ceramic coated in gloss black. So there is something to suit both men and women. And the best news? It never needs charging.
It's early days for Kerv, the Kickstarted NFC contactless payment ring which has safely passed its campaign target. Now available in seven colours, the simple and affordable piece of smart jewellery - for men and women - allows you to make payments, validate you on public transport and unlock smart locks. There's no alerts or fitness tracking - Kerv is focused on just a few key features - payments and ID.
The final retail price should be about £50 when the campaign ends. This could be the device to achieve what the bPay range has failed to do - bring wearables into contactless payments in an intuitive and accessible way.
Ringly is widely regarded as the leader in the smart jewellery arena. This is largely due to the fact that the ring looks like an actual piece of jewellery that we'd wear - there are no obvious visual clues marking it out as a gadget.
Wisely, Ringly has kept it simple, with no screen, just subtle notifications from your smartphone, allowing you to choose what comes through - whether that's emails, texts, social updates or reminders from health or parenting apps. Plus you can even choose just to hear from certain people.
The company is also currently working on smart bracelets - hopefully they can produce something more desirable that the slightly gaudy Swarovski Shine. Look out for a Ringly review on Wareable soon.
This modular smart stone can be worn as a bracelet, pendant or a large but stylish smart ring. It buzzes when your phone gets alerts from priority contacts and messages with special key words in, letting you get on with the rest of your day without being bothered by news or any other notifications that you don't care about.
Our Altruis smart jewellery review said: "It might essentially have 'just' one function but what it can offer - peace of mind while still staying hooked up to the internet - is arguably much more likely to improve your life than say, ten questionable smartwatch features."
The Smarty Ring makes some pretty big claims, basically aiming to pack all the technology you'd expect in a smartwatch into a ring.
A tiny screen shows notifications from your smartphone as well as allowing you to make outgoing calls to preset numbers, control music and even trigger the camera. It also functions as a digital watch, charges wirelessly and looks awesome.
The catch is that the Smarty Ring doesn't appear to have shipped yet, despite reaching its funding target in December 2013. We sincerely hope it's a real product and not just vaporware.
Available in "two majestic colours" - that's black or white - this ring links up to your smartphone via Bluetooth and vibrates to notify you of incoming texts, emails and social alerts.
It has a tiny screen where you can scroll through notifications, but the size means there's not much room for a great deal of meaningful information.
We've seen this ring up close and the photos don't really reflect the fact that it's not actually round - it's more of an oval shape with flat ends, making it extremely bulky. It's difficult to imagine a less discreet smart ring.
Too big and rectangular to really be considered a fashion friendly piece of smart jewellery, Vring isn't just the wrong form factor, it has some questionable features too. The Kickstarter campaign focuses on voice control which is a bit odd as there's obviously no display to show results or options as on a smartwatch. At $129 it's not cheap either and Kickstarter backers seem to agree - funding was cancelled after just $1,434 was pledged and the company plans to rebuild its campaign. Vring may work as a smart home controlling accessory but we'd have to try it out to be convinced.
The most simply named smart ring possible got less than favourable reviews on its release – in fact it was dubbed one of the 'worst wearables in history'. We think that's a little unfair - we've seen worse.
Crowdfunded on Kickstarter by makers Logbar, the Ring uses gesture controls to perform numerous useful tasks like controlling your smart home gadgets to some not-so-useful ones, like controlling your smartphone (when it's right in front of you).
Manufacturing and testing delays followed by a less-than-perfect product meant that backers weren't happy with the final product but we have to admire the ambition of the makers and we reckon it won't be the last we hear from them.
This is the smallest wearable technology in the world for measuring emotions, says its maker. It pairs with a smartphone app to give you instant feedback on your mood and emotion levels by measuring your electrodermal activity (EDA). The palm side of your finger is the optimal place for a reading, so if the ring rotates on your finger (as all rings do), you won't get an accurate measurement.
Created by one of Scandinavia's top jewellery designers, the ring looks good though the clearly visible micro USB port on the side does spoilt the aesthetics somewhat.
We're sure there's a market for this but for us, wearing a piece of jewellery that is constantly monitoring how stressed we are sounds about as soothing as a Dalek relaxation tape.
The work of Palo Alto-based Fin Robotics, this thumb ring lets you control any smart device by moving your thumb over your fingers. By recognising different segments of your fingers it can convert your palm into an alphanumeric keyboard, just in case that's something you ever wanted to do.
In fairness, though we can't see this catching on with a general audience it may well have some useful applications for blind people.
The technology at work here is actually pretty clever but with a bulbous plasticky build, describing this gadget as "fashionable" is way wide of the mark. Really, they lost us at "thumb ring".
Imagine one of those jewel-encrusted 'class rings' that university graduates wear in the US. Supersize it. Now add a built-in rape alarm. You've just imagined the Siren.
Twisting the top of the ring 60 degrees to the left will activate an "unbearably loud alarm" designed to deter any would-be attackers. To manually turn off the alarm after (hopefully) thwarting a physical attack, you must carry out a baffling combination of 6.5 rotations of the ring.
While we genuinely applaud the idea behind this invention - to keep ladies safe in potentially dangerous situations - we can't say we're keen on the design or the practicality of having an attacker alarm built into a ring.
This bad boy has been around for a few years and was designed to offer a smaller, more convenient alternative to the chest strap-based heart rate monitor.
And it's not just a heart rate tracker. No, sir. This retro smart watch also boasts a clock and a stopwatch.
We have a soft spot for the clunky, retro design, but it appears to be entirely impractical. And who wants to exercise while wearing a giant comedy ring? No one, that's who.
This gesture control ring is designed for multiple uses including gaming and controlling your smart home - apparently it works with all LG smart TVs built from 2012 onwards.
The waterproof housing is home to two CPUs and because the software is open source, it's open for developers to come up with applications for all sorts of platforms including iOS, Android and Oculus with suggested uses including virtual reality gaming and the piloting of drones.
The technology is impressive, but the plasticky design isn't ideal. There's just no getting around the fact that Nod looks like a cock ring.