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Usability Testing

Mobile Payment App — Usability Testing

Usability Testing Study · Financial Services Company · 2023

10
Participants
9
Tasks Tested
3
Metrics Measured
18–45
Participant Age Range

Overview

A moderated usability testing study evaluating the new design of a mobile payment application before launch. The goal was to measure how easily and intuitively users could complete key tasks, and to identify critical usability issues that — if left unaddressed — would have caused significant drop-off in production.

Research Goal

Evaluate how simple and usable the new design of the mobile payment application is for real users across a range of core tasks — and identify what needed to change before the app could go live.

Research Approach

  • Format — In-person moderated sessions combining interview and usability testing
  • Participants — 10 participants, ages 18–45, mix of existing and non-existing app users
  • Session duration — 10 to 20 minutes per session
  • Tasks — 9 tasks covering core app functions

Metrics Measured

Error Rate
Ratio of failed tasks across all users
Time on Task
Average time spent completing each task
Effort Score (CES)
User-rated difficulty per task (1 = very easy, 5 = very hard)

Tasks Tested

  • Pay a utility bill using 3 different paths
  • Pay a city cleaning fee using 3 different paths
  • Change app language to English
  • Add a service to favorites
  • Remove a service from favorites
  • Transfer money by phone number
  • Subscribe to notifications
  • Request money
  • Copy account number

Key Findings

Home Page

  • The oversized card component was mistaken for a promotional banner by most participants and ignored entirelyMajor
  • Categories displayed directly on the home screen would significantly reduce navigation frictionObservation
  • The offers and promotions section created visual clutter and competed for attention with core functionsObservation
  • Transfers, payments, and requests worked better as a unified space rather than three separate sectionsObservation
  • Optimal home page priority: 1) Cards, 2) Frequent services, 3) Categories, 4) TransactionsObservation

Navigation & Bottom Menu

  • Bottom menu icons without text labels were consistently misidentified by participantsMajor
  • Too many menu items created confusion — participants struggled to find the right sectionMajor
  • Reducing the menu to 4 sections would improve discoverability: Home, Transfer & Request, Transactions, TemplatesObservation

Utility Payments

  • Search was the most successful path — fast, intuitive, and completed without errorsObservation
  • The payment path via the bottom menu completely failed across all participantsCritical
  • Showing the last payment or template when entering a utility provider would improve task completion speedObservation
  • The extra step of selecting a service after choosing a provider was unnecessary and created confusionMajor

Favorites

  • Saving only a service name proved insufficient — participants needed subscriber numbers and balance saved tooMajor
  • The process of adding to favorites was too complex and failed across all participantsCritical
  • The swipe-to-delete gesture for removing favorites was not discoverableCritical
  • Favorites functionality needed to extend to transfer contacts, not just servicesObservation

Money Transfer

  • Transfer via the main button was completed successfully by all participantsObservation
  • Transfer via the bottom menu completely failed — the path was not discoverableCritical
  • The "Card to card transfer" label caused consistent confusion — participants did not understand what it referred toMajor
  • Card balance should be visible during the transfer flow to support decision-makingMajor

Money Request

  • The money request feature was completely undiscoverable through the bottom menuCritical
  • The icon was not intuitive — participants could not identify its functionMajor
  • Card selection on the amount entry screen confused participants — they mistook it for selecting the recipient's cardMajor

Account & Card Page

  • The "IBAN" label was unfamiliar — participants consistently responded better to "Account Number"Major
  • Participants expected to see card balance on the card details page — its absence was a repeated pain pointMajor
  • A unified transaction view with filters across multiple cards would better match how participants think about their financesObservation

Key Recommendations

Card size reduced
Participants consistently mistook the full-width card for a promotional banner
Text labels on all bottom navigation icons
Icons alone were not self-explanatory
Last payment or template shown in utility flow
Removes unnecessary steps and speeds up task completion
Transfer and Request merged into one section
Their separation caused complete task failure
Favorites updated to save full payment details
Saving service name only had no practical value
"IBAN" replaced with "Account Number"
The technical label was unfamiliar to participants
Card balance shown during payment and transfer flows
Its absence caused confusion and hesitation
Bottom menu reduced to 4 items
Current structure had too many competing options
Success notifications moved to bottom with auto-dismiss
Top placement was frequently missed
Redundant service selection step removed
Provider selection was sufficient
UX writer collaboration recommended
Copy and label issues were present across multiple flows

Outcome

This research study had a direct impact on the product. The application had critical usability failures across multiple core flows — the money request feature was completely undiscoverable, key navigation paths had 100% error rates, and several labels and interactions caused consistent confusion among participants. Had the app gone to production without this research, it would have faced significant user drop-off and a poor experience at launch.

My findings and recommendations were taken on board by the product and design team, who used them to address the identified issues before release. The research effectively prevented a flawed launch and ensured the application went live in a significantly improved state.

Skills Used

Usability TestingModerated ResearchError Rate AnalysisTime on TaskUser InterviewsData Analysis & InsightsMiro