The latest brand to test the marketing potential of augmented reality is Guess Watches, which unveiled its new iPhone app this morning.

It’s called GUESSWatches, and is a free download from the App Store. Billed as an “iApp”, it includes news, product information, stockists details and promotions, as well as a QR reader function.

The AR element isn’t in the app yet, but will be added in an update in early October. It will tie in with a promotion called the Great GUESS Giveaway running in stores nationwide, kicking off on 6 October with an all-day event at Guess’ Regent Street store in London.

Customers who download the app and point it at the promotional boards will be able to watch videos of the brand’s latest watch collection, then either win a watch or a voucher to be used in-store that day.

At the launch, Guess told me that the AR technology itself is “mainly bespoke”, although it was originally based on Unity. In other words, this doesn’t appear to be a partnership with an AR startup like Aurasma, Blippar or Zappar.

We’re often quite sceptical about branded AR apps – mainly because a lot of them are useless. In this case, we can see the logic behind what Guess is doing. The AR elements pull people in with the promise of free stuff, but once the app is on people’s phones, regularly-updated content and canny use of push notifications are likely to be the most effective features.