Product Design Case Study · 2024
Look Mom,
no need to enter the supermarket!
82% of supermarkets are not adapted for people with reduced mobility. We designed Mercaorder — a kiosk system that lets you shop without stepping inside.
My role
Product Designer
Team
4 designers
Timeline
1 week · Design Sprint
Methods
Design Sprint · UX Research · Prototyping
Tools
Figma · Maze · Miro
01 — The Problem
Supermarkets are not ready for people with reduced mobility
People with mobility limitations face significant barriers when shopping at physical supermarkets. From users with crutches after accidents, to parents with strollers, to people with back pain — the current shopping experience excludes those who need it most.
We set out to understand the real depth of this problem before designing anything.
82%
of supermarkets are not adapted for people with reduced mobility
100+
aisles a person with crutches must walk through
3
user groups: mobility-impaired, parents, people with pain
#1
workaround was avoiding in-store shopping altogether
"Supermarkets are not yet prepared for users with reduced mobility. Every shopping trip is a challenge."
— User interview participant
02 — Research
We listened before we designed
We used the Design Sprint methodology (Jake Knapp, 2010) to rapidly understand, prototype, and validate our solution with real users in just five days.
Monday
Sprint Questions & HMW
How Might We questions, clustering, voting, and mixing User Persona with User Journey.
Tuesday
Lightning Demos & Crazy 8s
Rapid ideation with Lightning Demos, Crazy Eight exercises, and low-fidelity wireframes.
Wednesday
Art Museum
Heat map voting and storyboard with final design decisions.
Thursday
Prototyping
High-fidelity prototype in Figma (1920x1080 Full HD) with complete user flows.
QR over biometrics
Users prefer QR access over facial recognition for privacy and simplicity.
Large touch targets
The kiosk must have large components for users with limited dexterity.
Delivery matters
Home delivery is as important as in-store pickup for many users.
Guest checkout
Users want to shop without creating an account or sharing personal data.
"The touchscreen at the supermarket entrance must have large components to be accessible."
— Key insight from user research
03 — The Solution
One core flow. No noise.
Mercaorder Kiosk is a desktop-type touchscreen integrated at the supermarket entrance, designed with large components to facilitate viewing and use for everyone.
Select products → Choose pickup or delivery → Confirm and pay — all without entering the store.
We used a MoSCoW framework to ruthlessly prioritise and avoid scope creep.
Key design decisions
Decision 01
Large touch components
Minimum 48px touch targets to ensure accessibility for users with limited dexterity or coordination issues.
Decision 02
High contrast UI
WCAG-compliant color contrasts to ensure readability for users with visual impairments.
Decision 03
Simplified checkout
Minimum number of steps to complete a purchase, reducing cognitive load and frustration.
Decision 04
Guest checkout option
Users can complete purchases without creating an account, reducing barriers to adoption.
04 — Testing & Iteration
We tested early and learned fast
We tested the prototype with 6 people aged 35 to 67, all with some form of mobility limitation. We measured task completion, error rates, and user satisfaction.
Success
85.7% task success rate
Most users completed purchase flows correctly. Above our 80% target threshold.
Problem identified
19.7% failed clicks
Some buttons were too small. We increased touch targets by 25% after testing.
Insight
Average time: 204.8 seconds
Within acceptable range for a first-time user completing a full purchase flow.
Validation
High perceived usefulness
Despite minor UX friction, users rated the concept 4–5/5 for usefulness. The problem was real.
Based on testing, we restructured touch targets for better accessibility, simplified the delivery selection flow, and added clearer progress indicators throughout the purchase process.
05 — What I Learned
Product thinking starts before the first sketch
Key takeaways
Empathy should be paramount
Designing for accessibility benefits everyone — parents with strollers, elderly people, and those with temporary injuries benefit from the same solutions designed for permanent mobility limitations.
Design Sprint for rapid validation
Five days to go from problem to tested prototype. The sprint forced focus and prevented endless iterations on the wrong solution.
Test with real users early
Low-fidelity testing revealed problems we hadn't anticipated. Early validation saved weeks of rework on the wrong design.
Universal design is good design
Solutions built for people with disabilities often become the best solutions for everyone. Large buttons, clear feedback, simple flows — these benefit all users.
What's next
The next iteration would include voice recognition for users without use of arms, augmented reality to show products in situ, and partnerships with supermarkets for pilot implementation.
Mercaorder could be built as a real product today with current technology. The retail accessibility gap remains largely underserved — and that's the opportunity Mercaorder was designed to fill.