I can't see that walking around the store looking at your phone is in any way a different or better experience than pushing round a trolley and selecting the items physically rather than digitally.
It's a gimmick.
I know a lot if peoe will probably use it when it's first launched and it will gain some publicity, but in the long term it will probably be consigned to the dustbin.
But technology can help retailers, but in the places that make a difference. Apps and mobile versions of retailers websites are a great way to engage your customers in your brand, your stores and your offers (without the reported cost of the John Lewis system above of £100,000.) Poundland sends incentives to customers to Pinterest, Tweet and Facebook their experiences and their purchase and this makes headway into social media networking markets. Friends may not immediately run out to Poundland upon reading about it, but will bear them in mind on their next trip to the High Street. It's this kind of social media networking that is making unseen inroads into customers spending habits. The retailers with the best apps, best online offering and best social media links will probably win out over those that have great stores, but no more than that.
Click and Collect plays a massive part in this, and retailers of all shapes and sizes have become aware that they can still make the sale, even if the product us not in stock. Pay today and collect tomorrow, whether the buyer is in store, sat at home on a computer or browsing on their mobile phone is a great way to ensure that the business stays within your company - and that people don't shop around and look elsewhere. All retailers need is for the collection process to be smooth and streamlined to ensure that customers feel confident to follow the process again.
I witnessed a customer this morning in an unnamed High Street national chain go to the till to collect her parcel. The cashier asked her to wait while she found the delivery, and came back 2 minutes later to state that it wasn't there. Irate customer asked cashier to have another look and said that they wouldn't be doing this again. Cashier found item, but by this time there was a queue at the till, so the customer had to wait her turn to be served. All of this could and should have been much slicker and customer-friendly. A dedicated collection point, cashiers that are really clued up about their systems and an attitude of ownership of the situation make a great in-store collection experience.
Hope this helps.