A revolutionized shopping experience

Migrating the app to a modern technology stack, we helped create a futureproof solution supporting rapid innovation, A/B testing and the regular release of new features. With more than 100,000 reviews and a 4.7 star rating, the app has received exceptional user reviews for its ease of use and accessibility standards.

This retailer generates more than £55 billion in annual revenue and serves more than 80 million customers every week through physical and digital stores. They were one of the first to market an app revolutionizing grocery shopping in the UK and generating more than £1 billion every year.

While the app had evolved and improved from its origins, the technology stack remained dated, limiting the customer experience and pace of improvement.

The app allows customers to:

• Shop their favorite products in a few seconds and make changes to orders on the go.

• Restock their kitchen cupboards using a barcode scanner.

• Add products instantly from previous orders for easier repeat shopping.

• Arrange delivery seven days a week or arrange to click and collect.

Around 15% of the world’s population live with some form of disability. This is why building truly accessible digital products and embedding these requirements early in development is so crucial.

The joint team took advantage of native accessibility tools to ensure the app was able to reach and serve a large portion of their customers with vision impairment or physical disability.

Besides adopting accessible color combinations and legible text sizes as standard, we designed flexible layouts that enabled us to intelligently support dynamic text sizing. App content was structured logically and optimized for mobile screen reader technology (TalkBack and VoiceOver) to make it easy to use via switch control.

The app proved its robustness, withstanding a surge in demand during the COVID-19 pandemic. Its accessible design also has proved vital in ensuring the app serves today's most vulnerable customers.

A co-sourced team of designers, engineers, agile delivery leads and testers worked in close collaboration. As a distributed team across India and the UK, the high levels of collaboration and team unity were facilitated through key ways of working:

• A one-team mentality. We encouraged responsibility and technical ownership across regions and built team meeting cadences to fit both time zones.

• Communication. Representatives from both locations were involved in decision-making from the get-go, ensuring conversations and ownership were not siloed by location. This ranged from low-impact decision-making on acceptance criteria to larger decisions around timelines and communication to C-suite stakeholders.

• Feedback loops. We held regular interactive retrospectives with online boards and worksheets to ensure we captured feedback on ways of working and processes across locations.

• Breaking cultural barriers. Simple team bonding activities such as “Take a photo on your way to work” or “If the last sprint was a film, which film would it be?” succeeded in creating camaraderie and reduced potential barriers caused by cultural disparity.

Developing the app natively using Swift (iOS) and Kotlin (Android) enhanced the user experience for customers while ensuring the app was easy to maintain for the client’s internal teams.

A modular architecture allowed features to be plugged in and swapped out with ease. Common modules are already in use across the client’s other apps. Maximizing reusability enabled us to implement new features — and entire new apps — at a pace that their stakeholders had not seen before.

For users, a bespoke design was created for each platform, making the app more familiar and palatable.

Additionally, building across two code bases allowed the team to keep platform-specific logic completely separate. It also meant development was faster, as the team could take advantage of a range of native components across both platforms.

This benefited the team when building the first iterations of the app, and this set up the apps to be easily maintained for years to come. It also allowed us to take advantage of changes to each platform without waiting for the cross-platform framework to be updated.

We played a key role in helping the client grow their engineering team and capabilities by assisting in the interview process of hiring new engineers, coaching in agile practices and ways of working.

In order to measure improvement and development, the team had been tracking data for more than 18 months since the beginning of the project. Particularly important indicators included cycle time — enabling the average speed of tickets to be tracked from in development through to completion and throughput. This data was used in numerous ways, including:

• Tracking progress and forecast timelines. This wealth of data facilitated forecasting and communicating timelines to stakeholders with a high degree of confidence, based on previous trends and historical data.

• Speeding up internal processes. The data provided the team with context for retrospectives, enabling them to identify a block in peer review. Through remedying the peer review principles and analyzing the data, we were able to halve the time it took to move tickets through the column, reducing the overall cycle time by 40%.

• Increasing team morale. Tracking the cycle time and throughput motivated the whole team to improve performance. They could see in numbers when they were improving or slumping, gamifying the approach to our development process and encouraging the team to actively speed up.

We successfully futureproofed the app by using native components that will enable the internal team to develop new features and keep the apps up to date with new releases. We provided a solid foundation for future development of new features, form factors that were all A/B tested with business insight capability built in.