How to Build a Fintech App: Features, Compliance & Development Cost (2026)

Types of Fintech Apps (and Their Different Requirements)

Before planning your architecture, define which fintech category you are building — each has different regulatory and technical requirements:

Type	Examples	Key Compliance
Digital wallet / payments	Wise, PayPal	PCI-DSS, Money transmitter licence
Neobank / challenger bank	Monzo, Revolut	FCA/OCC bank licence or partner bank
Investment / trading	Robinhood, eToro	FCA, SEC/FINRA authorisation
Lending / BNPL	Klarna, Affirm	Consumer credit licence, FCA
Personal finance / budgeting	Mint, YNAB	Open Banking (PSD2), Plaid integration
Crypto	Coinbase	FCA crypto registration, FinCEN MSB

Core Features for a Payment / Digital Wallet App

• Account creation with KYC (ID verification, selfie, proof of address)
• Bank account linking (Plaid in US, Open Banking in UK/EU)
• Send and receive money (P2P transfers)
• Bill payments and scheduled transfers
• Spending categorisation and analytics
• Virtual and physical card management
• Transaction history with export
• Multi-currency support
• Biometric authentication (Face ID / fingerprint)

Compliance Requirements You Cannot Skip

PCI-DSS: If you store, process, or transmit card data, PCI-DSS Level 1 or Level 2 compliance is mandatory. Use Stripe or Braintree to handle card data (they are PCI-DSS compliant) and never store raw card numbers.

KYC/AML: Know Your Customer checks and Anti-Money Laundering monitoring are legally required for any money movement product. Use providers like Jumio, Onfido, or Sumsub for automated ID verification.

GDPR / CCPA: Financial data is highly sensitive personal data. Data residency, right to erasure, and consent management must be built into the architecture from day one.

Security Architecture Essentials

• AES-256 encryption for data at rest; TLS 1.3 for data in transit
• JWT with short expiry + refresh token rotation
• Rate limiting and fraud detection (velocity checks, device fingerprinting)
• Segregated environments (production card data isolated from development)
• Regular penetration testing (quarterly minimum)
• Immutable audit logs for every financial transaction

Technology Stack

Layer	Technology
Mobile	React Native
Backend	Node.js or Java Spring Boot
Database	PostgreSQL (ACID compliance is critical for financial data)
Cache	Redis
Payment infrastructure	Stripe or Adyen
Banking connectivity	Plaid (US) / TrueLayer (UK/EU)
KYC/AML	Onfido or Jumio
Fraud detection	Sift or custom rules engine
Cloud	AWS (with data residency controls)

Development Cost

Phase	Duration	Cost
Discovery, compliance planning	4–6 weeks	$15,000–$25,000
MVP (wallet + transfers + KYC)	6–9 months	$120,000–$250,000
Full product	12–18 months	$300,000–$500,000+

Build your fintech product with a compliance-first team. Schedule a consultation → or contact us to start your fintech project.