Mint Mobile · Lead UX Researcher

Redesigning navigation menus: an IA revamp to drive a 2.8% increase in cell phone plan sales

A research-led initiative to optimize site navigation and improve content discoverability through user-centered information architecture.

Open Card SortUsability TestingA/B TestingBehavior AnalysisHeuristic EvaluationOptimalSortMiroContentsquareBaymard Institute
Timeline
June 2024 – Nov 2024
Company
Mint Mobile
Role
Lead UX Researcher
Participants
20 participants
Stakeholders
Senior Director, VP, AVP of Product
Current navigation on mintmobile.com after research

Background

A B2C wireless provider with an outdated main navigation

Mint Mobile is a B2C wireless provider with no physical stores, so the website is the main storefront and support hub, making intuitive navigation key to user success. The main nav plays a crucial role in helping its broad audience, including many older, less tech-savvy users, get to key actions like choosing a plan or finding help. However, it hadn't been updated since 2020. I was brought in as lead UX researcher to lead a full redesign of the site's information architecture.

The Problem

Navigation lacked proper and relevant categorization

Key content was buried and unimportant pages were over-emphasized, making it difficult for users to find what they needed.

Previous navigation design
Previous design
What's working
  • Top-converting pages were left-most and most accessible
What's not working
  • Help / About pages weren't categorized (e.g. Coverage, How it Works, Why Mint), leading to overall clutter
  • High-converting blog pages the content team aimed to boost for SEO weren't included in the main navigation, despite strong performance
  • Account management pages (Activate, Log In) were inconspicuous

Research Goals

Create a more intuitive structure grounded in mental models

As lead UX researcher, I was responsible for:

  • Uncovering users' mental models of current navigation content via open card sort
  • Analyzing click behavior on current navigation to inform which pages should be prioritized
  • Conducting a heuristic evaluation to align the navigation with UX best practices
  • Proposing a new navigation variation that synthesizes qualitative and quantitative findings
  • Collaborating with the CRO team to A/B test the proposed navigation against the current one

Open Card Sorting

20 participants completed an open card sort

To better understand how users naturally categorize site content, I conducted an open card sort using OptimalSort with 20 participants. The sort used pages already in the existing navigation, plus additional pages outside the core purchase funnel that still strongly influenced purchasing decisions.

Card sort interface
Card sort interface, participants grouped and labeled 20 pages
Pages included in the card sort, with conversion rates and page views
Additional pages of interest gaining high traffic and performance

Card Sort Results

Four clear user categories that felt most intuitive

8 of 19 participants paired the same cards together at least 50% of the time.

How users grouped navigation content

While these groupings were helpful, I still needed to compare them with real site data to make sure they matched how actual users think and behave.

User Behavior Analysis

Site behavior showed users engaged with Plans, Log in, and Cart

Using Contentsquare, a behavioral analytics platform, I looked into site click data from the past 30 days. Clicks, hovers and attention metrics showed which links users engaged with the most and least. There was high interest in Log In, Shop Plans, and Cart and low engagement with Why Mint, How It Works, Help, and Coverage pages.

Click rate metrics from Contentsquare
Click rate metrics from Contentsquare

Synthesizing this data with card sort results, I knew that on top of the common groupings of card sort: Plans, Phones, Self Service and About, I needed to provide easy click access to Plans, Login and Cart in the proposed design.

Heuristic Evaluation

Previous design did not follow main navigation design principles

Leveraging Baymard Institute HCI studies, a repository of large-scale UX studies based on real user testing and HCI principles, I explored proven guidelines for main navigation design to guide my wireframe of the new layout.

Key takeaways were:

  • Using clear, easy-to-understand labels
  • Separating utility links (like Sign In, Track Order) from core shopping links

I shared these studies in conjunction with my proposed structure to the design team, who used them to build the hi-fi prototype for the new navigation.

IA Recommendation

The new design reflected clear before and after purchase pages

Based on user behavioral data, card sort findings, and best practices, I wireframed a design synthesizing all methodology-based findings.

Wireframe of recommended IA

Key changes:

  • Before-purchase pages like Plans, Phones, and About were grouped on the left side of the logo with clear dropdowns
  • After-purchase pages like Account, Login, and Activate were grouped with Cart on the right side.

This structure allowed for clearer content grouping and improved wayfinding.

A/B Testing and Results

The redesign lifted conversion by 2.8%

To validate the new navigation, we launched a 10-day A/B test comparing the previous design (control) with the new design (863,585 visitors saw the previous experience, and 864,429 saw the new one).

+2.8%overall conversion (408 additional plans sold)
+2.6%more visitors clicked "Add to Cart" after landing
+2.1%rise in plan purchases
+12.3%increase in BOGO plan purchases

Within 90 days, the redesign contributed to 10,495 additional plans sold.

Key Challenges

Complex data needed to be made stakeholder-friendly

First time experimenting with card sort. It was easy to take results at face-value, but I needed to remember that how external testers conceptualize pages might not represent the needs of our site visitors. It is a good starting point to have a baseline of groupings without bias of a real prospect's needs, but it was still important to cross-reference it with data that represented a greater population.

Creating recommendation that also matched business needs. I realized that my final wireframe would completely change the navigation of pages on the site. I had to discuss the proposed changes with the business to make sure that I wasn't hiding pages that brought the most traffic and revenue. This involved being in direct communication with analytics counterparts throughout the process before final proposal.

Simplifying complex visualizations for stakeholders. The card sort results offered complex visualizations (e.g. dendrograms, matrices, etc.) It would have been too overwhelming to showcase all the results, so I had to extract the most critical information and simplify so others could easily grasp the insights.

Reflection

A simple research methodology with big impact

This project was the websites first information architecture revamp and it was fulfilling to see how shifting links to be more visible or hidden could directly impact the user journey. The process of conducting a card sort, to leveraging analytics data, to wireframing a design recommendation was a process that increasingly challenged my analytical and creative thinking mindset. It was interesting to see how a simple testing concept could make such strong impact on the usability of the site and business metrics.