Hi, I’m Estelle Cai
I design for how people think, feel, and behave.
Product Designer blending psychology, research, and technology to build thoughtful digital experiences.
Featured projects
Research-led work, from first interview to final interface.
WaitPass
A pharmacy waiting assistant that turns prescription wait time into clear status updates and optional, relevant shopping.
Role — Product Designer Read case study →LUMO Time
A warm screen-time companion that helps people understand their phone habits and change them without strict limits.
Role — Researcher & Product Designer Read case study →GrowMind
An AI mentorship platform that gives psychology students clear, human guidance through three mentor roles.
Role — Researcher & Product Designer Read case study →Second Conversation
A school and home service that helps parents and teachers talk with children about sex education with confidence.
Role — Researcher & Service Designer Read case study →How I work
Three habits that show up in every project.
Start with the mental model
I map what people believe is happening before I decide what the interface should show.
Design for the emotional moment
Trust, doubt and relief shape decisions as much as clarity does, so I design for them on purpose.
Measure what people do
Interviews tell me why. Behavior data and testing tell me whether the design changed anything.
Experience
Design, research and product work across fintech, education and health.
Designing SAC Nexus, a pre-launch B2B AI investment platform: KPI drill-downs to partner, risk and deal detail, CRM-sync and pipeline workflows, and reusable interaction patterns for engineering.
Led 6 co-design sessions with children and raised workshop story completion from ~40% to ~80%. The framework was adopted by a festival with 50,000+ visitor engagements.
Shipped posting, commenting, mention and reporting features for a health-lifestyle community app. Cut the reporting flow from 5 steps to 3.
Ran a field study across 15 rural schools (300+ surveys) and turned the findings into mental-health training used by 50+ teachers.
Education
Where psychology met design.
- Interaction & UI design
- Wireframing
- Prototyping
- Design systems
- Accessibility (WCAG)
- Universal design
- Usability testing
- Contextual inquiry
- User interviews
- Co-design
- Surveys
- Thematic analysis
- Data analysis
- PRDs
- Journey mapping
- Success metrics
- Design QA
- Design handoff
- Figma
- Figma Make
- HTML
- JavaScript
- Python
- Claude
- ChatGPT
- Cursor
I’m Estelle, a product designer who studies people as closely as pixels.
I studied psychology at Mount Holyoke and now study learning engineering and HCI at Carnegie Mellon. I bring what I learned about motivation, emotion and perception into design, and I aim for experiences that feel calm, intuitive and supportive. I’m currently a UI/UX design intern at Summer Atlantic Capital.











