Nudge
Helping people notice the purchases they would want to reconsider.
Context
University of Washington MHCI+D
Ideation Studio Concept, Fall 2025
Team
Layomi Akinrinade
We all functioned primarily as interaction and visual designers.
My role
Research synthesis, interaction design, personalization and permissions, interactive prototyping
Project status
Concept with two rounds of interactive Figma prototypes. Sensing, purchase detection, and payment integration were not built. Independent continuation in progress since October 2026.
Product Overview
A financial companion for more considered spending
Nudge combines spending history, short check-ins, and prompts at the moment of purchase. It helps people see patterns in what they buy and pause on a purchase when something about it deserves a second look.
It connects three moments: checking in on how you feel, considering a purchase before you complete it, and reflecting on spending afterward. A prompt can show a similar recent purchase or offer to revisit an item tomorrow. In the app, a daily reflection and a mood-spending calendar let people add context to individual purchases and see patterns across a month.
[01B · Feature overview · Three readable screen crops captioned “Check in,” “Consider a purchase,” and “Reflect on spending.” An optional 10–15-second V2 clip can replace the third still.]
Problem Space: The Impulse Loop
Decisions often precede deliberate reflection
After a demanding day at work, mental and emotional exhaustion sets in, weakening cognitive defenses. The user collapses onto the couch and scrolls through social apps. Attention narrows across algorithmic feeds until a sale banner surfaces: bright, urgent, and precisely timed. The justification materializes automatically: “I’ve had a long day. I deserve this.” Within minutes, one-click checkout closes the transaction before conscious evaluation can occur.
[IMAGE: The Impulse Loop Diagram — Five sequential steps mapping Exhaustion → Passive Scrolling → Algorithmic Sale → Justification → Purchase & Regret]
Spending decisions are routinely made in emotionally charged states shaped by stress, boredom, loneliness, and social media influence. While emotional state and social media exposure are primary catalysts for spending, they remain completely invisible at the moment of payment.
[IMAGE: Problem Intersection Model — Three-circle Venn diagram illustrating Purchasing Habits, Emotional States, and Social Media converging on the unexamined transaction moment]
Formative Research & Opportunity
People don’t just spend money—they regulate feeling
Secondary literature on affective coping (such as Spending as Social and Affective Coping frameworks) confirmed that emotional spending is primarily a psychological regulation strategy rather than a budgeting failure.
Primary user surveys and interviews corroborated this dynamic: while emotional spikes are brief, observable interaction shifts precede impulse buys. Because digital payment methods eliminate physical payment friction, interventions must happen in the brief window right before checkout to be effective.
[IMAGE: Research Synthesis Wall & Journey Map — Affinity mapping of user interviews alongside Enterprising Elijah’s emotional curve during late-night online purchases]
Grounding the persona: Enterprising Elijah (25)
To anchor design decisions, we situated user needs through Elijah, a 25-year-old tech sales representative living in New York City. Experiencing steady income and disposable cash, he aims to save and invest while balancing lifestyle spending. However, late-night fatigue and targeted equipment ads lead to impulsive reward purchases. Elijah needed non-judgmental guidance that protected his long-term financial goals without restricting his independence.
The market gap: Visible money, invisible emotion
Evaluating personal finance applications revealed two distinct gaps: Traditional Aggregators (Monarch, Rocket Money, Chase) excel at categorizing transactions and tracking subscriptions, but remain entirely silent regarding the emotional triggers behind spending. Punitive Blockers treat users paternalistically, inducing shame and driving abandonment. The opportunity was clear: design an emotion-aware spending coach that introduces mindful pauses without guilt or control.
[IMAGE: Competitive Analysis Matrix — Detailed evaluation table comparing Google Sheets, Rocket Money, Monarch Money, and Chase Bank across tracking fidelity, emotional awareness, and autonomy]
Version 1: The Ambient Inference Architecture
Assuming passive sensing equals better intervention
The initial system architecture assumed that gathering continuous biometric and device telemetry would yield the most accurate predictions of impulsive states.
[IMAGE: Version 1 Product Architecture Diagram — Pipeline mapping wearable biometric data (EDA, heart rate) and raw device activity into automated contextual interventions]
The concept relied on wearable sensors to monitor physiological stress indicators (heart rate variability and electrodermal activity) alongside browser switching speed. When thresholds were reached, the system triggered an automated intercept dialog: “You are likely to make emotional purchases.”
[IMAGE: Version 1 Prototype Interfaces — Early mobile bank linking screen, raw transaction lists, and desktop warning modal dialog]
The Core Design Tension: Trust vs. Insight
More intelligence revealed customer hesitancy
Concept testing with users immediately revealed a fundamental tension with passive tracking:
Accuracy vs. Intrusiveness
Capturing high-resolution emotional and physiological signals required intrusive background monitoring that compromised psychological safety.
The Surveillance Paradox
When users felt monitored in sensitive financial scenarios, anxiety increased rather than decreased. Rather than feeling supported, participants worried their vulnerabilities were being tracked.
Biometric Ambiguity
Physiological signals lacked subjective context: “Biometric averages don’t represent me—I need to tell my own story.” An elevated heart rate could signify exercise, excitement, or a work deadline, not necessarily a pending shopping impulse. In sensitive personal domains, design must prioritize user trust and emotional dignity over automated predictive intelligence.
The Pivot: Ecological Momentary Assessment (EMA)
From passive sensing to user-controlled reflection
To address the trust paradox, the system was re-architected around Ecological Momentary Assessment (EMA) principles. Instead of continuously collecting biometric streams, Nudge pivoted to lightweight, voluntary self-reporting touchpoints.
[IMAGE: V1 vs. V2 System Pivot Diagram — Comparative diagram showing the shift from ambient biometric harvesting to user-controlled momentary reflection]
Operationalizing EMA principles in the interface
Non-Personal State Vocabulary
Replaced clinical diagnostic questions with neutral, visceral prompts such as “What’s your pace today?” and “What is your mind state right now?” using non-stigmatizing states: Clear, Foggy, Restless. Behavioral Inferences Over Vitals
Tracked observable actions such as rapid tab proliferation, session duration, and cart revisits to infer urgency rather than reading physiological data.
Progressive Disclosure
Eliminated upfront bank credentials and goal-setting demands during onboarding, introducing advanced data integrations only as trust is established.
[IMAGE: Version 2 Product Architecture Diagram — Revised data flow illustrating voluntary Emotion Journaling, Device Context, and Transaction Data feeding the Emotion-Spending Ledger]
Behavioral Inference & Systems Architecture
User-Reported State
Inferred Behavioral Pattern
Observable Interaction Signals
System Intervention Policy
Fast / High Energy
Stress & Urgency
Rapid add-to-cart clicks, single-session checkouts, high-value discretionary totals
Direct Pause: Introduce necessity prompts and suggest a short cool-down window.
Restless / Scattered
Boredom & Novelty Seeking
Tab switching, prolonged late-night feed scrolling, low-cost novelty items
Delay Reminders: Surface 24-hour hold options (“Revisit tomorrow”).
Foggy / Low Energy
Fatigue & Comfort Seeking
Late-night food delivery reorders, comfort shopping, repeated cart revisits
Gentle Check-in: Remind user of daily limits and present restful alternatives.
The refined behavioral engine translates qualitative momentary states into contextual rules without transmitting raw personal logs off-device.
Design Principles
Reflect, Don’t Restrict
Interventions introduce a conscious pause rather than hard payment blocks or friction barriers
Support, Don’t Shame
Replace deficit-oriented reprimands with positive reinforcement that celebrates restraint and intentionality.
Visible Data Provenance
Every behavioral insight clearly indicates the underlying input that triggered it, eliminating hidden automated deductions.
User Agency Over Automation
Users select their preferred intervention cadence and data inputs, retaining complete control over notifications and account visibility.
Core Product Experience
[IMAGE: Interface Evolution Comparison — Side-by-side progression showing the visual evolution of Bank Linking, Daily Spending Reflection, and the Mood-Spending Calendar from V1 to V2]
Low-Friction Daily Check-Ins
Users calibrate their emotional baseline through sub-5-second interactive sliders and state selectors, logging mental pace and clarity without cognitive burden.
[IMAGE: Daily Check-in Interfaces — Pace slider, Mind State selectors, and Energy Level prompt]
Contextual Check-Out Intercept
When shopping patterns indicate potential emotional urgency, Nudge introduces an optional pause at cart checkout. Rather than disabling the buy button, it presents a supportive decision branch: "You bought a similar item recently. Do you want to revisit tomorrow instead?"
[IMAGE: Cart-Level Contextual Intervention — Desktop browser extension overlay and mobile checkout intercept card]
Daily Spending Reflection & Mood Calendar
Visual summaries shift focus from product marketing imagery directly to price impact and emotional context, helping users review how weekly spending correlates with subjective feelings.
[IMAGE: Spending Reflection & Mood Calendar — Weekly expenditure versus mood states alongside a monthly statement summary]
Positive Reinforcement: The Skipped Purchases Catalogue
Traditional financial apps emphasize budget deficits and mistakes. Nudge flips this dynamic by cataloging items the user intentionally delayed or resisted. Users can review total "rescued dollars" (e.g., $240 saved from emotional late-night browsing) alongside upcoming 24-hour reminder holds, reinforcing deliberate agency.
[IMAGE: Skipped Purchases Catalogue & Money Milestones — Resisted items, reminder holds, and positive milestones]
Evaluative Findings & Future Trajectory
What testing revealed
Trust Precedes Insight
Prompting users for intimate financial or emotional disclosures before establishing product value results in immediate abandonment.
Less Data Can Yield Better Design
Replacing complex biometric instrumentation with simple, manual self-reports increased user trust and task completion.
Positive Reinforcement Fosters Engagement
Visualizing saved amounts and paused items generated higher motivation than categorizing budget mistakes.
What remains open
Longitudinal Behavior Change
Prototype-based evaluations cannot determine whether non-blocking pauses sustain effectiveness over months or succumb to notification habituation.
Alternative Urge Management
When a user chooses not to purchase, the app must provide healthier real-time replacement activities to help regulate the underlying emotion.
Point-of-Sale Integration
Exploring voluntary payment integrations (such as a Nudge card buffer) that allow users to enforce self-imposed cool-down windows directly at payment terminals.
[IMAGE: Final Showcase Presentation Hero — Clean multi-surface display summarizing Nudge’s reflective framework, brand identity, and mobile touchpoints]
Nudge shifted from an ambient predictive system into a transparent tool for self-awareness—demonstrating that in sensitive behavioral contexts, interface design should empower people to recognize their own patterns with dignity.