Rapidly delivering a new service for a high street icon

TAB partnered with Marks & Spencer to develop the Mobile Pay Go service. The service revolutionises the in-store experience for M&S Food customers, enabling users to beat the queues by scanning products, paying and leaving the store in one seamless experience. Working collaboratively, the TAB and M&S team built the service ready for a live employee trial in just 12 weeks.


Marks & Spencer is undergoing a significant transformation as they seek to place digital at the heart of their business, which includes investing in digital and mobile technology that will help improve the customer experience in-store.


"Retailers try out ‘digital first’ a lot. Firstly, let’s be clear, the world of mobile is here and we need to lead with ‘mobile first’ to connect with our customers and colleagues in a mobile, agile way” 

Steve Rowe

CEO, Marks & Spencer


Led by Jim Cruickshank (Global Head of Digital Product and UX), the Marks & Spencer team identified an opportunity to deliver on this vision for a ‘mobile-first’ shopping experience by enabling customers to pay for items in-store using their own devices, removing the need to queue. The perfect opportunity presented itself to pilot the new service when a new store opening at its Waterside Head Office was confirmed for summer 2018, but time was short.

Identifying the right partner

With M&S’s development teams engaged on other projects and accelerated timelines to hit, the team decided to look for external suppliers who had:

M&S quickly recognised that TAB fit this brief and we joined forces, with TAB Engineers, Testers and Product Owners complementing an M&S Product Owner and Designer. Over the following 12 weeks, the team delivered this high-profile innovation project ready for the launch of the new store.

M&S Mobile Pay Go

The M&S app, integrated with the Sparks loyalty program, detects when customers are within an M&S store and triggers Mobile Pay Go functionality. Customers can use the app to scan product barcodes with their device camera, which are added to the app basket. When the customer is ready to pay, they can make one-tap payments using their stored cards or Apple Pay.

Delivering quality at pace

Three key elements enabled the team to deliver the service at pace.

Close collaboration across the team
TAB Engineers collaborated closely with M&S Product and UX teams to provide continuous feedback and tight iteration loops to ensure a quality experience for customers. An example of this can be seen in the payment experience. When testing an early prototype, the team found it was almost too easy to pay, and users were tapping and paying before they had completed their shop. As a result, the team switched to a swipe across interaction to prevent mistaken payments.

Native front-end best practice
The requirement to deliver the service through the core Marks & Spencer app required some creative thinking to minimise the impact on the existing iOS development team while ensuring a smooth integration. The team identified that by building the front-end service as a separate framework on iOS, they could develop and test it independently before it was integrated and deployed to the main M&S app for the trial.

Adopting M&S technical standards
The team deployed and ran everything in Azure and M&S’s Kubernetes cluster, including an API built by TAB to handle payments and completion of transactions in M&S systems. Following M&S's latest technical standards and closely collaborating with M&S engineers and product managers ensured quality and ease of handover to the team who are now supporting the service.

The results

The service was successfully trialled at the opening of the new Paddington store, delivering a seamless experience for colleagues that want a quick pay and go option, just 13 weeks after we started working together. The service allows customers to scan and pay for items in under 10 seconds. Next for the service is further iteration based on customer feedback, launch into more stores and on Android devices.


"We teamed up with TAB to help us deliver on our product vision in a very tight timeframe. I was impressed with the team’s hands-on-approach and highly collaborative way of working with our designers and product owners. The team worked exceptionally well within our complex organisational and technical architecture to deliver a high quality customer experience, fast. As a result, we were able to launch the Mobile Pay Go service after just 12 weeks of development” 

Jim Cruickshank

Global Head of Digital Product & UX, Marks & Spencer

Next case study:


View case study