It’s the Apple app store’s fifth birthday today – Retail Week takes a look at how apps have changed retail since their inception.

From showrooming to mobile sales to niche services, apps have overhauled the way retail operates. Without them, the mobile channel wouldn’t have become the growth engine it is, and shoppers would interact with retailers in entirely different ways.

While many of the best apps around have come from online operators – Amazon and eBay are obvious leaders – apps have also done more to link the online and offline worlds than almost any other technology.

Amazon started the process with its barcode scanning app. The service allowed customers to scan a product in a store and compare its store price to the Amazon price – it incensed bricks-and-mortar retailers, and led to the phenomenon of showrooming becoming widespread.

But some traditional retailers have fought back with their own quality apps. Argos’ has long been one of the best examples on the UK high street, with its emphasis on speed and convenience. Marks & Spencer, meanwhile, has focused on good quality execution. Tesco is another trailblazer and not just in the technology it has developed. The grocer took the unusual step of making its barcode app, which allowed shoppers to create shopping lists by scanning products at home, the subject of a major advertising campaign reflecting the growing importance of digital to the business.

Starbucks, meanwhile, has spearheaded the rise of mobile payments, and it’s this that will really start to impact the way people shop. David Oliver, a partner at PWC, says mobile payments will be the most important area of development for apps. “The really interesting developments will be around mobile payments. We will start to see apps that have all your credit card and debit card information.”

Mobile apps have played a central role in retail’s mobile revolution - in the next five years they are likely to become an increasingly crucial part of the shopping process.