Under Armour SpeedForm Gemini 2 Record Equipped review

The UA SpeedForm Gemini 2 Record Equipped rings in the new era of the smart shoe. Smaller sensors and smaller batteries means that your footwear will soon feed into the wealth of data collected by your favourite fitness platform.

And while not the first nor the most advanced, the UA Gemini 2 Record Equipped shoes are certainly a substantial notch on the smart shoe timeline. From the second biggest sports apparel company in the world, the metamorphosis from running trainer to smart wearable device is significant – and it's part of the new line-up of connected sports tech exemplified by the Under Armour Health Box.

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What's more, it points towards an untethered experience, where you can run free from a phone or watch, and let your shoes do the tracking.

Sounds great, but at $149.99 – and a premium of $30 over a standard non-smart shoe – there's a downside: what's more, the tech inside is doomed to die when you finally throw away your trainers.

So are the Gemini 2 RE's an essential pair of smart sneakers or a set of chronically connected clogs? We got them dirty to find out.

UA Gemini 2 RE: Design and features

Essentially a smartened up version of Under Armour's classic Gemini range, there's no nasty surprises in the design. Lightweight, sleek with plenty of heel cushion and support, we took to them with aplomb.

The all grey design hardly excites compared to some of the more extravagant Gemini trainers, but they're unisex, functional and that's what counts most here.

With any trainer, we'd advise trying them on in a store before buying, even if you track down the non-connected version first.

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So what do these smart shoes do? Well, a little on how they work first. The trainers connect to the MapMyRun app, which we tested a new beta version of. You add the trainers via the Apps and Devices, and they appear like any normal HRM sensor. When you shake the right shoe it fires into life and connects. Super easy.

Now it's important to state that that shoes work two ways, when connected to the phone app and untethered, and for some buyers, the distinction will be important – and the marketing literature doesn't QUITE make things clear.

When you go out for a run with the shoes and app connected you will get the following data: Time, distance, pace graph, elevation gain, a map of your route and cadence. It's a fairly standard mix that is matched by most GPS watches and phone tracking apps.

When you take the shoes out on their own, you get a different set of results.

The Gemini 2 REs will track time, distance, pace and split times, but incredibly, not cadence – which Under Armour told us was beyond the capability of the storage and battery life inside the shoe, and would only be tracked when the app came along for the ride.

UA Gemini 2 RE: Tracking and accuracy

So we know what they track, but how well do they do it? For the purpose of this section, we're going to talk about the shoes untethered – how accurate are they without your phone and its GPS prowess for company?

We know that the metrics tracked are distance, time and pace – all without GPS and even a stop/go button to help. Slip them on, start running and pair them up when you're back at home. And the surprise is, that they're fairly on the money.

We tried multiple runs at different paces and routes, some with big hills and some on the flat tested against a GPS watch and everything was useable. Yes, it wasn't bang on GPS, but even two GPS devices will generate some differences – and while the Gemini 2 REs had a slight tendency to over estimate, it was generally less than 200m over a 5km run. That's pretty impressive given that the shoes auto-detect when you run and finish – and that's normally including a cool down walk up our street to finish. Good going.

There's one final piece of pleasing data: a perfect build up of historical data about your shoe, how far you've run on them, and more information on when they're due for a change.

UA Gemini 2 RE: Missed opportunities

The real question here though is about whether this data is enough. The shoes are great and offer usable data from your run, untethered from you handset. But given the premium in price we spoke about, is this enough?

And we have to say, the data returned from the shoes is probably not enough to recommend forking out for them.

Pace, distance and time can be gleaned from pretty much any device. A free phone app or a sub-$100 running watch. Yes, the beauty of the UA shoes (and the smart shoe in general) is that you don't need another device, you can run free and unencumbered – and if that's what you want, then great. But stick $30 on the price of a pair of running shoes that last six months (maybe less for serious runners), and in two years you'll have paid for that watch. It's down to preference, but we hoped the smart shoe would offer more.

We'd love to know about where I strike in my footfall, the length of my stride, and crucially, whether any improvements can be made. But it's clear from the limitations of tetherless running that the battery constraints of adding sensors to a shoe are problematic. It's a shame as we wanted more.

UA Gemini 2 RE: The app

Under Armour's big tech play is about building an ecosystem, and the Gemini 2 plug into its newly acquired MapMyRun app. We could dedicate a whole article to MapMyRun – and we will soon – but to summarise here, it's a superbly complete app that's up there with the best in terms of features.

Standout features include the ability to see where other users have run in your area and pre-load routes, as well as create training plans for events, take part in weekly social fitness challenges and a whole lot more.

The feedback on runs is clear and concise, and the app does some good work when it comes to comparing key pace and cadence information together in charts.