How to Develop a Fintech App: Requirements, Costs, and Compliance in Brazil

The Fintech Market in Brazil: Opportunity and Complexity

Brazil is the largest fintech market in Latin America and one of the five largest in the world, with over 1,000 active fintechs according to ABFintechs' 2025 Fintech Report. PIX, launched by the Central Bank in 2020, processed over 50 billion transactions in 2025, representing the world's largest instant payment system per capita.

Developing a fintech app is substantially more complex than a conventional marketplace or management app. The difference lies in the level of regulation, security requirements, and the responsibility the company assumes when handling third-party money.

For those starting to understand development costs, read our complete app cost guide. To understand how to start smaller, see our guide on app MVPs.

Fintech Types and Their Regulatory Requirements

The Central Bank authorization process for a Payment Institution takes an average of 12-24 months and requires minimum capital of R$ 1 million to R$ 10 million depending on the segment. Many fintechs opt for partnerships with already-licensed IPs (banking-as-a-service) to accelerate go-to-market.

Essential Compliance Requirements

LGPD (Brazilian Data Protection Law)

Mandatory for any company processing personal data of Brazilians. For fintechs, exposure is maximum as the data handled includes financial data, identity data, sensitive data (credit score, income), and behavioral data.

Key implementation requirements: explicit and revocable consent per data type, DPO appointment (mandatory for medium and large fintechs), privacy by design architecture, data subject rights mechanisms (access, portability, correction, deletion), and a defined incident notification process (72-hour window to notify ANPD).

PCI-DSS

Required for any application that processes, stores, or transmits credit or debit card data. Key developer requirements: card data never stored locally on the device, card numbers and CVV tokenized before network transit, HTTPS/TLS 1.2+ exclusively for communication with processors, use of PCI-certified SDKs (Stripe, Adyen, Pagar.me), and annual penetration testing.

KYC/AML

All money-moving apps must implement: CPF + photo document verification (OCR + facial recognition), CPF validation via Federal Revenue API, OFAC/PEP list verification, suspicious transaction monitoring, and COAF reporting for cash transactions above R$ 10,000.

Essential Features by App Type

Digital Wallet / Payment App

Recommended Technical Architecture

Mobile (Frontend)

For fintechs, Flutter has shown excellent results. Its own rendering engine eliminates UI inconsistencies between platforms — critical in financial apps where consistency builds trust. Native biometric integration (Face ID, Touch ID, Android biometrics) is mature and tested in the Flutter ecosystem.

Alternative: React Native with new architecture (JSI) for teams with JavaScript experience. For apps requiring very deep integration with specific security hardware, native (Swift + Kotlin) is the right choice. Read our comparison: native vs hybrid vs cross-platform app.

Backend

• REST API or GraphQL: Node.js + NestJS or Kotlin + Spring Boot are the most common choices in Brazilian fintechs
• Database: PostgreSQL for transactions (ACID compliance), Redis for cache and sessions, MongoDB for event logs
• Message broker: Kafka or RabbitMQ for asynchronous transaction processing
• Event sourcing: stores each transaction as an immutable event — ideal for audit and reconciliation

Infrastructure and Security

• Cloud: AWS, GCP, or Azure with Brazilian region (data in Brazil, per LGPD)
• AES-256 encryption at rest for sensitive data
• TLS 1.3 in transit for all communication
• Certificate pinning to prevent man-in-the-middle attacks
• Jailbreak/root detection blocking financial features
• Code obfuscation to hinder reverse engineering

Payment Gateway Integration

Cost Estimate by Module

Total Cost Estimate by Fintech Type

FWC Tecnologia's Fintech Experience

FWC Tecnologia has experience in financial application development, including payment gateway integrations (Pagar.me), KYC flows with facial recognition, NFC payment apps, and financial management systems.

Our process for fintech projects: security-focused architecture from the discovery phase, integration with Brazil's main gateways and credit bureaus, production-tested stack (Flutter + Node.js/NestJS + PostgreSQL + Redis), and delivery of security documentation for regulatory due diligence.

If you are evaluating developing a fintech, the conversation needs to start at the regulatory scope before reaching the technical scope. Request a technical meeting with our team to map the specific requirements of your financial project. Also see our guide on essential questions before hiring a software company.