BudgetCart
0→1 Product Design · AI UX · Mobile App · Accessibility · Ethical Design · UMSI SI 582
Designing the moment before checkout.
A 0→1 grocery decision-support app that helps shoppers compare price, SNAP/WIC eligibility, dietary safety, AI recommendations, and store options before checkout.
Turned a broad grocery app concept into a tested decision-support prototype focused on affordability, eligibility, dietary safety, and trust.
Role
UX Research · Interaction Design · AI Flow · Budget Tracking · Testing + Iteration
Timeline
August 2025 - December 2025
Organization
Class Project
Tools
Figma — auto layout, variants, interactive prototyping
BudgetCart helps shoppers understand what is affordable, covered, and safe before they commit to a grocery purchase.
The one-sentence case
BudgetCart started as a grocery app, but became a decision-support system after testing showed that users did not just need fewer choices — they needed the right decision cues at the right moment.
The final product direction brings budget, eligibility, safety, AI, and store comparison into one shopping flow.
The problem
Grocery apps show products. Budget-sensitive shoppers need decision support.
Most grocery apps help users search, add items, and check out. But for shoppers balancing budget limits, SNAP/WIC eligibility, dietary restrictions, and store choice, the hardest part happens before checkout. They are not only asking "Can I buy this?"
Existing grocery apps
Existing grocery apps optimize for transactions, but budget-sensitive shoppers need clarity before they commit.
The 0→1 product opportunity
The opportunity was to make the moment before checkout clearer.
The opportunity was not to make checkout faster. We saw grocery shopping as a sequence of tradeoff decisions, not a simple purchase flow. For users balancing money, benefits, and health needs, every item can affect the rest of the cart. So BudgetCart was built around one product bet: budgeting should happen inside the shopping flow. Not after checkout. Not in a separate finance tab. Not in a different budgeting app. At the moment users are deciding what to buy.
Before: budgeting lived separately
Budget tracking sat apart from grocery decisions—users did the mental math while building the cart
After: budget inside shopping
Budget visibility while users browse, add items, compare stores, and review substitutions
Onboarding → Budget Dashboard → Product Browse → AI Cart Builder → Substitution → Checkout Compare → Receipt Scan. The product system moves decision support into the shopping journey instead of making users compare across separate tools.
My role
Connecting user uncertainty to interface decisions.
I worked across the research and design process, with deeper ownership over the AI cart-building and budget tracking experiences. I contributed to problem framing around affordability, benefits, and dietary needs; research synthesis and product requirements; AI cart-builder interaction design; the budget dashboard and budget calendar flow; usability testing and iteration planning; and translating testing breakdowns into interface changes.
My main contribution was deciding what information needed to appear, when it needed to appear, and how much guidance the product should provide without overwhelming the shopper.
Research focus
We were studying the hidden decision process behind grocery shopping.
Before buying, users were weighing price, store choice, food safety, dietary needs, benefits eligibility, time, convenience, budget limits, and trust in substitutions. That changed how we framed the product: BudgetCart could not just be a cart. It needed to be a decision layer.
Before: "Track spending later."
After: "Support decisions now."
Personas
Hi! I'm Jade, I'm 22 and an Office assistant. I am also a single parent.
Hello! I'm James. I'm 34 and a Part-time warehouse worker.
Budgeting happens item by item: users make small, repeated decisions while shopping—choosing cheaper items, skipping extras, checking totals, and wondering whether a substitution is worth it.
Research insights
Four insights shaped the product.
Each insight paired what we saw in research and testing with a concrete product decision.
01
Users were budgeting while shopping
Users made small budget decisions item by item. A separate budget dashboard was not enough—budget information needed to appear inside browsing, cart-building, substitutions, and checkout.
02
Eligibility had to appear before checkout
SNAP/WIC uncertainty creates stress. We surfaced eligibility on product cards, product details, and checkout comparison—benefits are primary shopping signals, not secondary filters.
03
AI needed a starting point
A blank input created uncertainty. We added upload/camera cues and starter prompts—AI UX needs guidance, examples, and feedback, not just a text box.
04
Simplifying too much reduced trust
Removing brands and prices made users less confident. We moved to item-first browsing with lowest-price visibility—less information became better-timed information.
Simplicity only works when users still have the cues they need to trust the system.
Signature design decision
Price transparency during substitutions.
Many grocery and delivery experiences hide substitution cost changes until later. BudgetCart makes that cost explicit before the user confirms: if a replacement item costs more, the interface tells the user what changed and what the new total will be. This is not just a UI detail—it is an ethical design decision. For budget-sensitive users, a small substitution can affect the rest of the cart. By showing the price impact upfront, BudgetCart prioritizes user control over a faster checkout.
Instead of hiding substitution costs, BudgetCart makes the financial impact visible before users confirm. Ethical design can be embedded directly into microinteractions.
Design evolution
From clean but unclear to simple and trustworthy.
Our biggest design tension was: how do we reduce cognitive load without removing the information users need to feel confident? Version 1 was category-first with no brand, no store, and no price—we thought less information would reduce decision fatigue, but users struggled to locate items and felt uncertain without price cues. Version 2 shifted to item-first browsing—users found items faster, but still lacked confidence without price visibility. Version 3 added lowest-price visibility while keeping detailed store comparison until checkout—users could browse simply while still seeing enough information to trust the flow.
V1 · Category-first, no price
V2 · Item-first, still no price
V3 · Item-first + lowest price
Reducing cognitive load does not mean removing information. It means showing the right information at the right moment.
Outcome
The impact was product clarity.
Because BudgetCart was a student prototype, I am not claiming launch or business metrics. We moved from a broad grocery app idea to a sharper 0→1 concept: a grocery decision-support tool for people balancing affordability, benefits, and dietary needs. The prototype demonstrates the user experience and decision logic; the next step would be validating feasibility through real inventory data, eligibility databases, and more robust error handling.
What the prototype explored
Reducing uncertainty around SNAP/WIC eligibility, making grocery budgets visible during shopping, comparing stores with less mental math, making AI cart-building easier to start, protecting users from hidden substitution costs, and treating dietary safety and affordability as connected decisions.
What I would do next
This project changed how I think about accessibility.
Accessibility is not only screen readers, contrast, and labels. In BudgetCart, accessibility meant price clarity, benefit clarity, dietary clarity, less mental math, and more control at the moment of decision. Helpful products do not just give users more information—they give the right information at the moment users need it.
Not after checkout. Not in a separate tab. At the decision.
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