Wearable payments make one of the strongest cases for smartwatches, and Android Pay is another way that Google is finally catching up to Apple.
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As it's only available with the new software update, Android Pay is currently very limited on wearables but Wear 2.0 is soon to roll out to more device, so it won't be long before it's more widely available.
Here's how it works, and who can use it.
Who can use it?
A limited few, sadly. While Android Pay is supported by most top banks, to use use it on your wrist you'll need an Android Wear smartwatch that includes NFC technology and is running Android Wear 2.0.
Right now that's the LG Watch Sport, the Huawei Watch 2 and the Tag Heuer Connected Modular 45. As for supporting banks, Google continues to bring new names onboard, and you can view an updated list of all the Android Pay-participating banks here.
How to set up Android Pay on your watch
If you've not already got Android Pay working on your phone, you'll need to set that up. To do this, download and open the Android Pay app - it's here where you can add a new debit or credit card to your account, either by scanning it with the camera or adding it manually.
You'll then need to verify your card with your bank, the process for which may vary depending on which bank you're with. However you do it - likely through text or email - you'll need a verification code that you can then enter into the Android Pay app to validate the card.
Next up, open up Android Pay on your watch and choose the option to add a new card. It will then direct you to your phone, where you should see your saved card(s); tap on the one you want, enter the security code, and accept the terms and conditions (not before giving them a good looking over, of course).
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Again, you'll have to verify your card with your bank using another code. Once that's done - if you haven't already done so - you'll be prompted to set up a form of security verification for your watch. You might not want a security mechanism at all, but Android doesn't let you use Pay without it, and you don't really want someone stealing your watch and running riot with your hard-earned cash, right?
So enter either a passcode or pattern and make sure you remember it. You won't have to enter it every time you use Pay, but if you've taken your watch off since you last made a transaction it will prompt you to verify yourself first.
Oh, and to delete a card just open up pay, tap on your card when it appears, then scroll down the page. At the bottom, drag up the options and hit 'Remove'.
How to use Android Pay
Once your bank card is paired with your watch, the rest is easy. On the LG Watch Sport and the Huawei Watch 2 you can use one of the side buttons as a shortcut for Android Pay and we expect many future Wear watches will offer something similar. You can scroll to Android Pay via the menu if you like, but it will take as much time as fishing out your wallet - so what's the point?
A single touch of the shortcut button - or a tap of a widget on your watch face, also an option - will instantly activate Pay. You should see a picture of your card and an instruction to 'Hold to terminal...'. Hold the watch up to the payment terminal as instructed and you're done.
And that's it. The only other possible step, previously mentioned, is entering your passcode if your watch needs to verify that it's really you before you splash out on $50 worth of Ben & Jerry's.
You don't need your smartphone with you to do this - and you don't need a SIM card inside a cellular-equipped Wear watch. Your smartwatch essentially stores the card and the payment point does the connectivity bit to your bank.
How it compares to the competition
The basic function of Android, Samsung and Apple Pay is the same across all three - tap the terminal to pay - but they differ when it comes to who supports what.
While Android Pay and Apple Pay only work with NFC terminals, Samsung Pay, featured on the Gear S3, also has MST (Magnetic Secure Transmission) meaning it can work at any terminal where you can swipe a debit or credit card. It also now works with non-Samsung Android phones. The downside? It's only available in the US for now, so UK has to wait a while longer to use it.
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