Do we need money transmitter licences?

For a custodial wallet holding customer funds, very likely yes in most US states. FinCEN and state money transmission laws apply to platforms that custody digital assets on behalf of users. Legal counsel is essential before you accept the first deposit, not after you have launched and onboarded users.

How do you handle private key security?

For custodial wallets, private keys are managed in hardware security modules or a KMS service such as AWS KMS, with multi-signature controls requiring more than one authorisation for high-value transactions. For non-custodial wallets, keys never leave the user’s device and the security model focuses on secure local storage and recovery flow design.

Can the wallet support multiple blockchains?

Yes. We build multi-chain wallets supporting EVM chains including Ethereum, Polygon, Base, and Arbitrum, plus Bitcoin and Solana where required. Each additional chain adds scope and we confirm which chains your users need during discovery rather than building for all of them speculatively.

How is this different from your Crypto and Web3 industry page?

The Crypto and Web3 industry page covers the full landscape: DeFi, NFTs, smart contracts, DAOs, and the regulatory environment broadly. This page is specifically about building a crypto wallet application — the custody models, the security architecture, the compliance requirements, and the cost.

Crypto Wallet App Development Company

A crypto wallet is one of the few applications where a security failure means the permanent, irrecoverable loss of a user’s funds. That is not a bug with a hotfix — it is the end of the platform. The wallets that survive in this market are the ones where every layer of key management, transaction signing, and user authentication was designed for the threat model from day one rather than hardened after the first incident.

For founders building in this space, the design challenge is the opposite of most consumer apps: simplicity at the surface over a security architecture that cannot be simplified. A wallet that is too complex to use correctly is abandoned. A wallet that simplifies the wrong things gets drained. Getting that balance right requires understanding both the cryptographic requirements and the consumer UX patterns that make a technically correct product one that people will actually use.

01

Asset Management and Portfolio

Multi-chain asset balances, transaction history, token management, NFT display, and portfolio value tracking across wallets and chains in one interface.

02

Security and Key Management

Private key custody architecture, multi-signature controls, hardware security module integration for custodial wallets, and biometric and MFA authentication for every access point.

03

Fiat On-Ramp and Off-Ramp

Credit and debit card purchase of crypto, ACH funding, and fiat withdrawal, integrated with licensed on-ramp providers so users can move money in both directions.

The platform holds private keys on behalf of users. More accessible for non-technical users, but requires a robust key custody infrastructure, KYC at onboarding, and likely money transmitter licensing.

Users hold their own private keys. Less regulatory exposure for the platform, but the UX must handle seed phrase management, key backup, and recovery in a way that does not result in permanent fund loss.

A read-plus-send wallet spanning multiple chains and accounts, where the primary value is unified visibility across a user’s full digital asset portfolio rather than custody of a single chain.

A user who has used Coinbase or MetaMask arrives at a new wallet with a reference point. They expect to see their balance update within seconds of a transaction confirming. They expect transaction fees to be shown before signing, not after. They expect recovery options to exist and work before they need them rather than being documented in a help article they find when funds are already inaccessible. Missing any of those three damages trust in a way that is very difficult to recover from.

The regulatory expectations for custodial wallets are moving quickly. A custodial wallet holding customer funds is likely a money transmitter under FinCEN guidance, requiring state-by-state licensing across the states where users reside. KYC at account opening and AML transaction monitoring are obligations that apply before the first deposit, not after the first examiner’s letter. We treat the compliance architecture as a design constraint from the first discovery session rather than as a legal opinion to obtain later.

05 features

Multi-chain asset balance and portfolio view
Send, receive, and swap with gas estimation
Transaction history and confirmation tracking
Fiat on-ramp and off-ramp with card and ACH
Biometric authentication and session controls

Core send, receive, and balance features for one or two chains without custody infrastructure. These typically fall in the mid five-figure range and take twelve to eighteen weeks to build.

Multi-chain support, fiat on-ramp, swap functionality, and portfolio tracking with a polished consumer experience. These sit in the high five-figure range with an eighteen to twenty-four week build.

Custodial wallets with HSM key management, KYC and AML infrastructure, money transmission compliance, and institutional-grade security. These run into the six-figure range and are scoped individually.

These are market ranges, not fixed quotes. We give you an itemized number after a short discovery call.

01Discovery

We map your custody model, your target user, your chain requirements, and your compliance obligations before any design decisions are made.

02Design

We prototype the send, receive, and recovery experience before development starts, testing the security interaction points and the seed phrase flows specifically.

03Development

We build in sprints with regular check-ins, with key management and security architecture built alongside the interface rather than reviewed at the end.

04Testing

Every build goes through security review and transaction flow testing on testnet before release so key management and signing logic are validated before real assets are involved.

We build crypto wallet apps in React Native for iOS and Android. Web3 interactions use ethers.js and viem for EVM chains, with chain-specific libraries for Solana and Bitcoin. Custodial key management integrates AWS KMS or a hardware security module provider. Fiat on-ramp connects to licensed providers including MoonPay, Transak, or Stripe. Smart contract interactions for swap and DeFi features use audited interfaces rather than custom contracts where possible.

React Native
TypeScript
JavaScript
Node.js
PostgreSQL
Redis
AWS KMS
Stripe
GraphQL
HSM
Google Cloud
Firebase

01

Security Architecture Reviewed Before Interface

02

Custody Model Chosen Before Development Begins

03

Compliance Obligations Mapped Before Onboarding

04

Independent Security Audit Recommended Always

A crypto wallet that holds real funds is a security product first and a financial app second. We treat the key management architecture and the threat model as the first engineering problems, not the last.

A crypto wallet that holds real funds is a security product first and a financial app second. We treat the key management architecture and the threat model as the first engineering problems, not the last.

A crypto wallet that holds real funds is a security product first and a financial app second. We treat the key management architecture and the threat model as the first engineering problems, not the last.

A crypto wallet that holds real funds is a security product first and a financial app second. We treat the key management architecture and the threat model as the first engineering problems, not the last.

01

Security Architecture Reviewed Before Interface

02

Custody Model Chosen Before Development Begins

03

Compliance Obligations Mapped Before Onboarding

04

Independent Security Audit Recommended Always

In a custodial wallet, the platform holds private keys on behalf of users, like a bank holds deposits. In a non-custodial wallet, users hold their own keys, and the platform cannot access or recover funds. The choice determines your security obligations, your regulatory exposure, and your recovery UX.

Crypto Wallet
App Development

Why The Crypto Wallet Market Needs The Right App