GAMMA & Karwei App

Project Overview

Context

GAMMA and Karwei wanted to rethink the role of mobile within the customer journey. While e-commerce performed well, the app lacked clarity, consistency and meaningful support during project preparation and decision-making.

The goal was to evolve the app from a transactional shopping tool into a supportive companion for inspiration, preparation and decision-making throughout DIY projects.

Role

As Product Designer, I helped shape the product direction from discovery through concepting and interaction design, collaborating closely with Product, stakeholders and developers throughout the project.

Outcome

Two redesigned mobile apps that help customers explore products, find inspiration and make more confident decisions throughout DIY projects.

Impact

• 763,962 additional downloads
• 335% increase in sessions
• 656% revenue growth
• App Store rating increased from 1.4 to 4.7

Research & insights

Research focused on understanding customer behaviour, in-store decision-making and the broader DIY journey across digital and physical touchpoints.

Customers primarily used the app during the orientation and preparation phases of DIY projects, exploring products, materials and inspiration before visiting a store.

A recurring insight was that many users lacked confidence when selecting products for a specific task. The app therefore focused on reducing uncertainty by helping users understand what they needed, why they needed it and what to do next.

The product needed to support both experienced DIYers looking for speed and users with limited domain knowledge who required more guidance and reassurance.

Concepts and Tests

Early concept testing revealed that users across all experience levels experienced uncertainty before, during and after DIY projects. Users needed clearer guidance around preparation, product selection and execution.

Supporting distinct user behaviours

The experience balanced two core behaviours: efficient product-oriented navigation for experienced users, and guided exploration for users seeking inspiration and reassurance.

Product Direction

The strategy focused on supporting customers throughout the lifecycle of a DIY project: from inspiration and preparation to purchasing and execution.

Inspiration and DIY guidance remained native to create a more contextual and supportive mobile experience. This allowed users to explore projects, calculate quantities and understand requirements before committing to a purchase.

The concept also explored giving DIY guidance and inspiration a more prominent role within navigation. Organisational trade-offs ultimately reduced their visibility, but the underlying interaction principles continued to influence the product’s evolution.

GAMMA

The DIY advice is the most significant part of GAMMA's proposition. Firstly, I analysed and mapped the current job information on the website, after which I created an alternative flow for the mobile experience.

Karwei

Karwei is the hardware store with taste. For this proposition, we want the apps to focus more on decoration and the associated inspiration.

A shared e-commerce base

While both brands shared a common e-commerce foundation, proposition-specific UX patterns helped differentiate GAMMA’s practical DIY focus from Karwei’s inspiration-driven experience.

App as learning vehicle

Insights from the native app informed improvements across the broader digital ecosystem, influencing both mobile and web experiences beyond the initial app concept.

Shop

In general, the shop pages like search, the product list page and the check-out flow are identical for all apps in terms of UX. At Karwei, images are more central because of the brand. For this reason the product list page is standard in a grid and with GAMMA in a list. In addition, the product detail page is also different due to the focus on product images at Karwei and the description at GAMMA.

Favourites

Favourites were designed to support both structured project planning and quick access during store visits, allowing users to save products, searches and colour references in lightweight shopping lists.

My-page

The My-page directly shows the customer card to scan at the counter, in addition to other remaining features.

Outcome & impact

The redesigned app expanded the role of mobile beyond transactional commerce by introducing inspiration, guidance and decision support throughout DIY projects.

It successfully supported both efficient product-driven shopping and more guidance-oriented customer journeys.

Measurable impact

Expanding the app beyond transactional commerce significantly improved engagement, conversion and customer satisfaction.

• 763,962 additional downloads
• 335% increase in sessions
• 656% revenue growth
• App Store rating increase from 1.4 to 4.7 stars

Broader impact

Although organisational priorities shifted over time, many of the concepts and interaction patterns developed for the app continued to influence the wider digital ecosystem.

Background & team

This project was developed within an interdisciplinary team at MakerStreet, collaborating with strategists, designers, researchers, copywriters and developers. My focus centred on product direction, interaction design and stakeholder alignment..