Multichain Crypto Wallet App Development

**Project Title:** Multichain Crypto Wallet App (Android & iOS) with Custom Blockchain Integration

I'm looking for an experienced blockchain/mobile developer or team to build a secure, non-custodial cryptocurrency wallet app for Android and iOS, similar in functionality to Trust Wallet (UI/UX will be provided separately — this project is focused on core wallet functionality and security).

Core Requirements:

1. Platform: Native or cross-platform app for both Android and iOS (React Native / Flutter acceptable if performance and security are not compromised)

2. Multichain Support: Wallet must support multiple existing blockchain networks (Ethereum, BSC, Bitcoin, Solana, etc. — final list to be discussed)

3. Custom Blockchain Integration: Must integrate support for our own custom blockchain network and its native coin (details and node/RPC access will be shared with the selected developer)

4. Security (non-negotiable):
- Non-custodial — private keys generated and stored only on the user's device, never on any server
- HD Wallet standard (BIP-32/39/44) — single seed phrase generates all addresses across chains
- Keys encrypted using secure device storage (Android Keystore / iOS Keychain)
- All transaction signing must happen locally on-device
- Biometric/PIN app lock

5. In-App Browser: Built-in dApp/website browser so users can connect the wallet to decentralized apps and websites directly within the app (similar to Trust Wallet's DApp browser / WalletConnect support)

6. Clean, maintainable codebase with documentation, since further features will be added over time.

7. Documentation: User guide + basic maintenance/support documents.

What I'll provide:
- Custom blockchain network details (node/RPC endpoints, technical specs)
- Native coin specifications
- Branding/UI assets (once development-ready)

What I'm looking for in a freelancer:
- Prior experience building crypto wallets or working with wallet SDKs (e.g., Trust Wallet Core, WalletConnect, ethers.js/web3.js)
- Experience integrating custom/non-standard blockchain networks is a big plus
- Strong understanding of key management and mobile app security best practices.

Please share relevant past work (wallet apps, GitHub, or similar projects) along with your estimated timeline and budget.