UI/UX Case Study · Mobile App

Yowza: replacing paper loyalty cards with a digital rewards & wallet experience

A frozen yogurt & ice-cream shop app — 23 screens, wireframes, a style guide, and a full design system, designed end-to-end in one month.

Role

Research · Persona · Survey · Wireframe · Final Design

Duration

1 month · 8-week plan

Deliverables

23 app screens, design system, 23 case-study slides

Tools

Figma, usability testing

Overview

Yowza Desserts wanted to boost customer engagement with a mobile app featuring a digital rewards system, simple payment options, and an interactive menu. My UX solution created a seamless experience while making the rewards and wallet features both fun and easy to use.

Goal 01

Brand-aligned design

Fun, vibrant, and easy to navigate.

Goal 02

Rewards system

Collect 18 stamps to earn a free dessert.

Goal 03

Mobile wallet

Quick pay, top-ups, and gift card sharing.

Goal 04

Personalization

Allergy filters and tailored offers.

The problem & the solution

Problem

  • Customers lost or forgot paper loyalty cards and missed rewards
  • Tracking stamps was confusing and time-consuming
  • Promotions were hard to discover in-store
  • Payment at the counter was slow and manual

Solution

  • A built-in rewards tracker replaces paper cards
  • Visible stamp progress with a free-dessert countdown
  • Promotions and offers in one place
  • Digital wallet for fast, contactless payment

Research

I conducted 20 user interviews with regular customers and observed in-store behaviour to see how people tracked rewards and paid. The survey confirmed a strong appetite for going digital:

Prefer a digital loyalty system over paper cards82%
Would visit more often if rewards were auto-tracked76%
Want real-time promotions & recommendations69%
Interested in a mobile wallet for top-ups & quick pay71%
Believe a dedicated app makes the brand feel modern84%

Define: empathy map & persona

Says

  • "I always lose my loyalty card."
  • "I wish I could see my rewards on my phone."
  • "Paying at the counter takes too long."

Feels

  • "It would be easier if everything was digital."
  • "I want a faster way to earn and redeem rewards."

Thinks

  • Frustrated about losing paper cards
  • Impatient with slow payments
  • Motivated by personalized offers

Does

  • Carries a paper card but often forgets it
  • Checks posters for promotions
  • Waits in line to pay manually
🍦

Emma Brown, 24

University student · visits Yowza weekly

"I love Yowza's desserts, but keeping up with paper stamps and missing offers feels old-fashioned. I just want everything in one easy app."

Goals
  • Track rewards & redeem free desserts easily
  • Discover promotions quickly
  • Fast, contactless payment
Pain points
  • Loses her paper loyalty card
  • Misses new offers
  • Counter payment is time-consuming

Information architecture

Card sorting and user flows shaped a five-tab structure where the key jobs — scan, top up, see offers — are always one tap away.

Home
Menu explanation
Learn more
View menu
Menu
Details
Prices
Differences
Scan
Scan code
Top up
Rewards
Offers
Wallet
Top up
Share gift card
Profile
Personal details
Allergy sheet
Log out

The design system

Color system
Primary Pink#FF6DC0
Navy Ink#102C5C
Cream Accent#FFFFDB
Success Green#66BB6A
Background#F6FBFE

Typography scale

DisplayWelcome to Yowza
HeadingYour Rewards
TitleCollect 18 stamps
BodyEarn rewards every time you visit us.
CaptionScan this code to earn points

Brand icon

yOwza yOwza Primary & secondary lock-ups — the "O" always carries the opposite brand color.

Components

Top Up Share Gift Card £10 View Menu Home Recipient's Email ✉️

Rewards stamp tracker · collect 18, get a free treat

🍨

11 of 18 stamps — 7 more desserts to a free small tub, milkshake, or smoothie.

Visual design

Three of the 23 final screens, recreated here as live previews — home, wallet, and scan-to-earn.

Hello, Mavis 👋
Frozen Yogurt & Ice-creamFind your flavor — fat free, gluten free, rich in calcium
🍧
RewardsCollect 10 more desserts to get rewards
🎨
Make it your own!10 flavors · 40 toppings · 1000 combos
🧇
Find your flavorMade with the highest quality ingredients
View Menu
HomeMenuCodeWalletSetting
Home
My Balance£100.00
Top Up Share Gift Card
£5£10£15£20£25
Special ice cream — Strawberry 🍓Luxurious strawberries in every serving
HomeMenuCodeWalletSetting
Wallet & top up
Welcome to the Yogurt shop — earn rewards every time you visit us
Scan this code to earn points
🍦
Claim free yogurtYour rewards
🧇
Claim free waffleYour rewards
HomeMenuCodeWalletSetting
Scan to earn

Testing & findings

Usability testing with 5 regular customers — register, check rewards, top up and pay, find and redeem an offer.

4/5
users immediately understood the digital rewards system
↑
"Top Up" button visibility improved after testing
+
guided tooltips added for first-time onboarding
Users said the all-in-one wallet and rewards integration made the app feel "clean and modern" — and the stamp countdown visibly increased motivation to return.

What I learned

User research directly shapes effective design solutions. Clear navigation and IA carry usability; feedback and iteration refine the experience; and good design balances user needs with business goals.

Next project

Kpopper Palace →