Secure mobile apps for wallets, trading and finance.
BitAzure builds iOS and Android applications with React Native for wallets, exchanges, DeFi protocols, fintech products and enterprise workflows, with biometric authentication, hardware-backed key storage, real-time data, offline resilience and a release pipeline that handles code signing and over-the-air updates.
- React Native for iOS and Android from one TypeScript codebase
- Biometric auth, keychain and secure enclave storage
- Real-time WebSocket data, push notifications and deep links
- App-store compliance, CI/CD, code signing and OTA updates
What is mobile app development for crypto and fintech?
Mobile app development for crypto and fintech is the engineering of iOS and Android applications that handle keys, money and market data on a device the user controls, which means the app must combine a responsive interface with hardware-backed security, resilient networking and a release process that satisfies app-store review. It spans UI, on-device cryptography, API integration, push and deep-link infrastructure, and the CI/CD pipeline that ships updates safely.
BitAzure builds these apps with React Native and TypeScript, sharing business logic with web products while using native modules where the platform demands it: secure enclave and keystore access, biometric prompts, background tasks and performance-critical rendering. The same team delivers wallet apps, trading clients, DeFi front ends, fintech products and internal enterprise tools.
Mobile is where users judge a financial product most harshly. Slow lists, dropped WebSocket connections, confusing transaction states or a rejected store submission cost trust immediately, so we treat performance profiling, offline behaviour and store compliance as engineering deliverables rather than final polish.
Mobile app development capabilities
From key storage to store submission, each capability is delivered with automated tests and documented platform-specific behaviour.
Cross-Platform Engineering
- React Native for iOS and Android with shared TypeScript logic
- Native modules in Swift and Kotlin where required
- Navigation, state management and design-system components
- Shared packages with web front ends via monorepos
- Device and OS version compatibility matrices
App Types
- Crypto wallet apps with self-custody or custodial models
- Trading apps with order entry, charts and portfolio views
- DeFi apps with wallet connectivity and transaction simulation
- FinTech apps for payments, cards, savings and onboarding
- Enterprise apps for operations, approvals and field workflows
Security & Device Features
- Biometric authentication with Face ID, Touch ID and Android BiometricPrompt
- Secure storage using Keychain, Keystore and the secure enclave
- Root and jailbreak detection, screenshot and overlay protection
- Certificate pinning and encrypted local databases
- Session management with device binding
Connectivity & Real-Time Data
- Real-time prices, order books and balances over WebSocket
- Reconnection, resubscription and gap recovery logic
- Offline handling with queued actions and cached state
- Push notifications via APNs and FCM with topic targeting
- Deep links and universal links for onboarding, referrals and transaction flows
Quality & Performance
- Performance profiling for startup, list rendering and animations
- Accessibility: screen readers, dynamic type and contrast
- Automated unit, component and end-to-end tests on device farms
- Crash reporting and in-app diagnostics
- Localisation and right-to-left layout support
Release Engineering & Compliance
- CI/CD for mobile with automated builds per environment
- Code signing, provisioning and certificate management
- Over-the-air updates for JavaScript bundles
- App-store compliance for crypto apps, including review guidelines and regional restrictions
- Staged rollouts, feature flags and remote configuration
Reference mobile architecture
The app is a thin, secure client: keys and sessions live in device hardware, data arrives through a gateway with real-time channels, and releases flow through a pipeline that separates native builds from over-the-air bundle updates.
Hover or focus a component to see its role in the architecture.
- Mobile App (React Native · TypeScript): Shared TypeScript logic with native modules for biometrics, secure storage and performance-critical screens.
- Secure Storage (Keychain · Keystore · biometrics): Hardware-backed key and token storage gated by Face ID, Touch ID or BiometricPrompt.
- API Gateway (REST · WebSocket): Device-bound sessions, request signing, rate limits and WebSocket fan-out to mobile clients.
- Push Service (APNs · FCM): Topic and user-targeted notifications for price alerts, transaction status and security events.
- Backend Services (Accounts · orders · wallets): Domain logic for onboarding, trading, transfers and balances exposed through the gateway.
- Real-Time Feed (Prices · balances · events): Aggregates market data and account events into resumable streams with snapshot recovery.
- CI/CD Pipeline (Build · sign · test): Automated native builds, code signing, device-farm tests and bundle packaging per environment.
- Chains & Indexers (RPC · indexers): Transaction broadcast, balance reads and event indexing across supported networks.
- Data Stores (PostgreSQL · Redis): Account state, device registrations, notification preferences and cached market data.
- Stores & OTA (App Store · Play · OTA bundles): Store submissions for native releases and signed over-the-air bundles for JavaScript updates.
Device
- UI and navigation
- Secure storage and biometrics
- Offline cache and queue
Edge
- API gateway
- WebSocket fan-out
- Push delivery
Backend
- Domain services
- Real-time feeds
- Data stores
Delivery
- CI/CD and signing
- Store submission
- OTA updates and flags
Mobile apps we build
Self-custody wallets
Key generation, backup and signing on device with multi-chain balances and transaction history.
Exchange trading apps
Order entry, charts, portfolio and alerts with real-time market data.
DeFi front ends
Swaps, lending and staking flows with wallet connectivity and simulation before signing.
Payments and neobank apps
Onboarding, KYC, cards, transfers and statements with strong authentication.
Enterprise and operations apps
Approvals, field data capture and dashboards for internal teams.
Loyalty and tokenised rewards
Consumer apps that expose tokens and NFTs without exposing blockchain complexity.
Why teams build mobile with BitAzure
One codebase, native behaviour
Shared TypeScript with native modules where platform features or performance require them.
Security on the device
Hardware-backed key storage, biometrics and tamper checks designed in from the first sprint.
Resilient real-time data
WebSocket handling that survives backgrounding, network switches and reconnects without stale views.
Store-review readiness
Compliance requirements for crypto apps are tracked from design to submission to reduce rejections.
Fast, safe releases
Automated pipelines with signing, testing and OTA updates for rapid fixes within platform rules.
Accessible by default
Screen-reader support, dynamic type and contrast checks built into the component library.
Technologies we use for mobile development
React Native
MobileNative iOS and Android apps from one TypeScript codebase.
TypeScript
FrontendStrict typing across the entire stack, client to contracts tooling.
Swift / Kotlin
React
FrontendComponent-driven UIs for dashboards, exchanges and wallets.
Node.js
BackendEvent-driven APIs, gateways and real-time WebSocket services.
PostgreSQL
DatabaseTransactional ledgers, ledgers-of-record and analytical workloads.
Redis
DatabaseCaching, sessions, rate limiting, pub/sub and order-book snapshots.
Ethereum
BlockchainMainnet and L2 deployments, account abstraction, indexing.
Solana
BlockchainRust programs with Anchor, SPL tokens and high-throughput dApps.
AWS
InfrastructureEKS, RDS, KMS, CloudHSM and multi-region deployments.
Docker
InfrastructureReproducible builds and images across every environment.
Kubernetes
InfrastructureAutoscaling, rolling deployments and workload isolation.
How we deliver mobile apps
Every engagement follows a documented, milestone-driven path from discovery to continuous development.
- 01
Product and platform discovery
User journeys, custody model, platform features and store constraints are defined, along with performance and accessibility targets.
- 02
Architecture and security design
Key storage, session model, API contracts, offline strategy and native module boundaries are documented and reviewed.
- 03
Design system and core build
A component library and navigation shell are built first, then feature screens are delivered against mocked and then live APIs.
- 04
Native integration and hardening
Biometrics, secure storage, push, deep links and tamper detection are integrated and tested on physical devices.
- 05
Testing, profiling and compliance review
Device-farm test runs, performance profiling and a store-guideline checklist precede submission.
- 06
Release and continuous delivery
Store submission, staged rollout, OTA pipeline and monitoring, followed by iterative feature releases.
Security practices in mobile development
Hardware-backed keys
Private keys and tokens stored in the secure enclave or Android Keystore, never in plain application storage.
Biometric and PIN gating
Sensitive actions require local authentication with fallback policies and lockout after failed attempts.
Transport security
TLS with certificate pinning, request signing and short-lived tokens bound to the device.
Tamper resistance
Root and jailbreak detection, debugger checks, obfuscation and secure screen flags where appropriate.
Secure update channel
OTA bundles signed and verified before execution, with rollback if a release fails health checks.
Privacy controls
Minimal data collection, clear permission prompts and analytics that exclude sensitive fields.
We coordinate independent third-party audits on request and never claim an audit, certification or compliance status unless it has actually been obtained.
What to decide before building a mobile app
Custody model
Self-custody puts key management on the device and the user; custodial designs shift it to the backend. This choice drives security, recovery and compliance work.
React Native versus fully native
React Native covers most financial apps well; fully native is justified for heavy graphics, specialised hardware or strict platform-specific requirements.
Store policy for crypto
Apple and Google apply specific rules to wallets, exchanges and token features, and requirements vary by region. Plan for them before design is final.
Offline expectations
Decide which screens must work offline, how queued actions are reconciled and how stale data is labelled.
OTA update boundaries
Over-the-air updates cover JavaScript changes only and must respect store rules; native changes require a full release.
Device diversity
Android fragmentation and older iOS versions affect biometrics, secure storage and performance; define a supported matrix early.
Mobile App Development questions
React Native lets one TypeScript codebase serve both platforms while still calling native APIs through modules. For most wallet, trading and fintech apps this gives faster delivery and consistent behaviour, and we write native code where the platform demands it, such as secure enclave access or high-performance rendering.
Planning a wallet, trading or fintech app?
Share your platform targets and custody model. We will respond with an architecture outline, a security approach and a release plan.