
Identifying, confirming, and addressing UX challenges with Zillow’s iOS app*
*Two notes: 1) Unlike the other “case studies” on my site, which come from companies I’ve worked for, it should be clear that I did not work for Zillow. 2) Several issues that I identified in this case study from 2018—which is notably more UX focused than the others—have actually been addressed since.
When my wife and I had our first baby, we had been considering buying a bigger home. There are a couple real-estate apps out there, and Zillow is perhaps the biggest. Yet we both had some issues using it. I wondered if anyone else was having similar issues.
I conducted a usability test.
I identified a few different UX challenges, but I ultimately focused on two (more on why below): filtering and the price slider. Here’s an example that shows why applying filters was non-intuitive:

Here’s how I went about my test.
Objectives:
- Observe users interacting with the Zillow iOS app.
- Identify user experience challenges.
- Categorize and then prioritize those issues.
- Explore alternative design solutions.
- Validate changes with additional user feedback.
Observe: Interview and Tasks
I interviewed seven people (although really just five people will help you discover 93% of what is possible to discover). A friend videoed each of these interviews, as users navigated and narrated their experiences.

I asked users to perform two tasks:
Imagine you’re in the market for a new house. You can afford something up to $900k and you’re looking in San Francisco. Can you show me how you would find a place in that range?
Then I adjusted the scenario:
You just found out you just won the lottery and can spend $5M! You also really like places right around our current location. How would you adjust your search?
Afterward, I wrote down insights from each interview. Each participant got a different color sticky so I could track who had which issues.
Observed issues:
This is a summary of the issues I observed.

Synthesize and Prioritize issues
Categorization of the aforementioned stickies helped to identify common issues or themes.

As shown, a couple of patterns emerged, some of them specific and some more general.
Next, I prioritized the issues. I put each issue on a 2×2 matrix that mapped importance to the business and to the user. This was how I ultimately chose which features to focus on and try to address.

User Goals & User Stories
In order to understand the context in which someone uses the Zillow app, I applied a modified version of the Jobs to be Done framework, USMO: Users / Situations / Motivations / Outcomes. This helps to break down user motivations and desired outcomes and understand why someone uses the app — what are they trying to achieve?
For the sake of this exercise, I narrowed down motivations to one primary one:

Personas & Scenarios
Persona
I also looked at a 2016 National Association of Realtors (NAR) survey, which provides demographic data about home-buyers, such as income and marital status.
I used USMO and the data to create a proto-persona to represent a common Zillow user: Jared. Then I created a related scenario.


Scenario
Jared is looking for a house with his wife. They are expecting a baby and want more space for themselves and their dog. They aren’t sure what they can afford or where to look, so they use Zillow to browse by a variety of criteria. Based on what they find, they prioritize their criteria and create a list of houses to start looking at.
A related task flow is shown to the right.
Exploring alternative solutions
Lo-Fi Sketches
With a good sense of user challenges and intended objectives, I began to consider

Prototyping and Validation
From paper, I moved to Sketch. Once I had updated designs, I created a clickable prototype, in this case using Marvel. Using this, I once again asked people to go through the same tasks.
Comparing Before and After:

Validation Testing
How effective were my changes? I asked seven more people to perform the same tasks with my prototype. This time, I observed none of the issues I had previously.

Conclusion
Zillow may have had other reasons for the design decisions they made*; as an outsider, it’s always hard to know. But a combination of testing and industry experience suggests that these changes would improve UX— ultimately increasing app engagement (time spent) as well as total searches completed.
*As noted at the start, Zillow has actually addressed the biggest challenges identified here since the time this was written—which is a neat sort of validation for me as well.