Mascot UX · Fintech·2026

Cuak — Your emotional financial companion

Most people feel their credit is fine — until suddenly it isn't. Cuak is a fintech mascot that reacts to credit health in real time, replacing financial anxiety with actionable clarity before the crisis happens.

UX / Product Design
React Native · Belvo · Node.js
3 Core Screens
Testers felt more in control
Cuak — cover

App screens currently in final iteration — will be updated here as they're completed.

Most people feel their credit is fine — until suddenly it isn't

Bank dashboards show numbers — balance, limit, due date — but never answer the real question: am I okay? That uncertainty creates anxiety instead of action. Cuak makes the warning visible before it becomes a crisis.

The result: silent distress, reactive behavior (paying only the minimum out of fear) and total disconnection from the financial product.

The problem

Banking apps are technically correct but emotionally cold. Users know how much they owe; whether that puts them in a good or bad position stays unanswered, and the uncertainty paralyzes them.

A mascot that reacts to your financial behavior

Cuak connects to credit card data via Open Banking (Belvo) and maps user behavior to one of four emotional states. The mascot's state is the primary interface: it occupies the top of the screen and drives everything below it.

Three core screens designed and working:

Home

Current mascot state + billing cycle summary. Users understand their situation in under 3 seconds.

Progress

Financial behavior history, rendered as trends the user can read at a glance.

More

Settings, account connection (manual or Belvo), alerts and notification preferences.

+ Installment calculator — implemented

Opens from the front card of the deck. The user enters an amount and number of installments with a vertical sliding selector. Calculates in real time: monthly payment, total paid, total interest and amortization table. Uses the card's real rate or estimates from usage level. Blocks the calculation if the amount exceeds available credit. The entry animation uses Reanimated — it reveals below the deck without interrupting the gesture.

+ Card deck with gesture animations

The card deck uses react-native-gesture-handler + Reanimated on the UI thread. The user swipes down to change the front card. Animations run off the JS thread — no frame drops during gestures.

Four states. One clear signal.

The system maps the user's financial behavior to four emotional states. Each state has a visual expression, a color and a suggested action — reducing the cognitive friction of interpreting financial data.

Cuak waiting
Waiting
No cards added yet. Initial onboarding state.
Cuak happy
Happy
Low credit usage. Everything in order.
Cuak watchful
Watchful
Medium credit usage. Worth keeping an eye on.
Cuak worried
Worried
High usage. Billing date approaching. Action recommended.
Cuak alert
Alert
Very high usage. Limit maxed out or overdraft risk. Cuak reacts before the user makes the mistake.
Waiting Waiting
Happy Happy
Watchful Watchful
Worried Worried
Alert Alert
Data (left)
60%
Objective financial information: balance, used limit, billing date
Emotional state (right)
40%
The mascot and its state — the signal the user reads first

Cuak advises you before you spend

Banking apps tell you what you already spent. Cuak shows you what you should do before making the decision. The Purchase Simulator is the product's flagship feature.

The user enters the amount of a future purchase — a TV, a trip. The backend engine (cycle_service.py) analyzes the billing cycle and responds with the optimal strategy.

If you buy tomorrow

50 interest-free days

One day after the billing date = a full new cycle. Cuak warns you before you make the mistake.

● The behavioral loop

If the user makes the smart decision, Cuak rewards them instantly. If they try to overdraw, Cuak switches to Alert state before the mistake happens, so the limit arrives as a face they recognize rather than a figure they have to interpret.

From Apprentice to Credit Master

Good financial decisions generate Experience Points (XP). This positive reinforcement turns debt payment from a stressful chore into a rewarding experience — the same mechanism that gives Duolingo 40M daily active users.

+20 XP Low balance — keeping credit usage below 30% of the available limit.
+50 XP On-time payment — paying before the due date, regardless of the amount.
+100 XP Optimal decision — using the Simulator and choosing the strategy Cuak recommends. The behavior the whole product exists to create.
Apprentice
Apprentice
0 – 200 XP
Building base habits
Aware
Aware
200 – 500 XP
Understands their billing cycle
Planner
Planner
500 – 900 XP
Uses the simulator before buying
Strategist
Strategist
900 – 1400 XP
Optimizes purchase windows
Strategist Pro
Strategist Pro
1400 – 2000 XP
Zero mistakes across 3 straight cycles
Credit Master
Credit Master
2000+ XP
Zero-risk lead for banks

Behavioral Scoring and B2B Lead Generation

Cuak flips the traditional banking model. Instead of charging users for their financial mistakes, Cuak charges banks for their best customers.

B2C — Freemium

$9.99 / month

Premium plan with unlimited simulations, multi-card analysis and advanced proactive alerts. The free plan includes 1 card and 3 simulations per month.

Projections grounded in behavioral design

A 0-to-1 project — no real users yet. No existing fintech product uses a mascot as the primary emotional signal for financial data: Nequi and Greenlight have friendly UX, but no reactive emotional layer. Duolingo proved that anthropomorphism drives retention — Cuak applies that mechanism to personal finance for the first time. The projections start from that gap.

+70%
Estimated Day 30 retention
vs. the ~25% benchmark for generic finance apps. Mascot anthropomorphism and the fear of "breaking the streak" of XP build a daily open habit.
Lower churn through cognitive clarity
The 60/40 rule (data left, emotion right) removes the cognitive load of interpreting financial information. Less confusion, less churn.
Pre-qualified B2B conversion
Leads reach banks only once the user hits verified behavioral maturity, so the bank buys a qualified lead rather than a slice of the whole base.

What prototype testing revealed

5 testers. 1 clickable prototype. 1 session each. Before a single line of production code — the behavioral design was validated.

"It feels like the app is on my side, not judging me."

— Prototype tester, session 3

Small sample. Real signal. Industry data backs the direction: gamification improves retention up to 30% (Deloitte). This prototype suggests the mechanism works — at scale, those numbers become revenue.

Built to scale with Open Banking

The stack was chosen to support future integration with banking data. The MVP currently runs on a custom backend calculation engine and mock data to validate the user experience and the behavioral design. The architecture is ready to swap those mocks for the real connection in the next phase.

Mobile Expo SDK 52 · React Native 0.76 · TypeScript · Expo Router · Zustand · TanStack Query
Gestures / Anim. React Native Gesture Handler · Reanimated (UI thread, useSharedValue, withSpring)
Backend FastAPI · SQLAlchemy async · Pydantic · Alembic · APScheduler (workers)
Infra PostgreSQL · Redis · Docker Compose · pnpm workspaces (monorepo)
Open Banking
Belvo — endpoints implemented, BelvoWidget integrated in mobile Sandbox phase
Design Figma · Expo Secure Store (token persistence)

From MVP to Production Integration

The emotional state system is designed and the simulator's core flow works in isolation. The next strategic steps are:

  • From Mock Data to Open Banking
    Finish the exploratory phase and sandbox testing to connect the Belvo API in production — real-time ingestion and sync of the user's transactions.
  • Testing with Real Users
    Measure whether Cuak's emotional signal actually curbs impulsive purchases against real banking data, not mocks.
  • Deploying the Emotional Scoring
    Turn validated behavior into a B2B data layer attractive to banks and financial institutions.
  • Sponsored Rewards Marketplace (Loyalty Program)
    The internal XP economy will evolve into an ecosystem of tangible rewards. Through B2B partnerships with banks and merchants, Credit Master users can redeem their points for real-world perks — movies, restaurants, in-store discounts. The differentiator vs. traditional points programs: rewards are earned through disciplined financial behavior, not spending volume. For the partner brand, CAC is minimal — direct access to a user with verified credit health and real purchasing power.

The visual system behind Cuak

Every emotional state, color and component is codified into a reusable system — palette built for emotional clarity, the 60/40 zoning model, and a full UI kit.

Explore the full Cuak Design System → 4 emotional states, palette, zoning model, core UI components and type system.

Building a fintech product that needs to feel human?

The emotional system behind Cuak can adapt to any financial or complex-data product. Let's talk.

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