Send USDC. Pay the fee in USDC. Hold zero gas.

self-custody · USDC-native · multi-network · testnet-first

Download on the App Store Coming soon
GET IT ON Google Play Coming soon

Why it's different

No more “you have USDC but can’t move it because you have no ETH”. Pay fees in USDC. Send with USDC. Bridge with USDC. Just have USDC.

Pay fees in USDC. Forget gas tokens.

Hold only USDC. Send USDC and the network fee is paid in USDC. No ETH. No SOL. No more running around topping up native gas just to move your stablecoins.

Just USDC is enough.

Other wallets strand you: you have USDC but can't spend it because you have zero gas token. Sigma9 North Star mode removes that tax. If you have USDC, you can send.

Real USDC across chains.

Move canonical USDC with Circle CCTP v2. Burn on one chain, mint on the other. No wrapped tokens. No synthetic versions. Real USDC arrives.

Self-custody without the pain.

Keys live only on your device. Face ID + mandatory PIN. Auto-lock. No backend ever sees your funds or can sign for you.

What we actually shipped

Gasless (North Star) stack

  • Pay the network fee in USDC, hold zero native gas token
  • EIP-7702 upgrades the self-custody seed-EOA in place (same address) to a Simple7702Account — no new smart-contract account, no migration
  • Submitted as one ERC-4337 v0.8 UserOperation via a Pimlico bundler
  • Circle Paymaster v0.8 fronts the gas and pulls USDC back via an EIP-2612 permit (no upfront approve, no ETH needed)
  • Same-chain gasless USDC send and gasless cross-chain — both through one shared submit engine

Cross-chain — Circle CCTP v2

  • Canonical USDC burn → attestation → mint (not a wrapped bridge)
  • Approve + depositForBurn batched atomically in a single gasless UserOp on the source
  • Circle Iris attestation polling; destination mint auto-forwarded on L2s (Circle Forwarding Service) or self-submitted on Arc
  • Optional Fast Transfer (soft finality) vs free standard finality

Networks (testnet-first)

  • Arc testnet — Circle's chain where USDC is the native gas coin (18 decimals). Balance from ArcScan.
  • Arbitrum Sepolia — USDC + USDT as ERC-20 (6 decimals); gasless via Circle Paymaster
  • Base Sepolia — USDC as ERC-20; gasless via Circle Paymaster
  • Solana devnet — USDC + USDT as SPL tokens (Classic mode)

One unified EVM address across all EVM chains; separate Solana address. Mainnet gated behind "Coming soon".

Self-custody & Wallet UX

  • BIP39 12-word seed; HD derivation (secp256k1 / ed25519); stored only in iOS Keychain (WhenUnlockedThisDeviceOnly)
  • Face ID + mandatory app PIN (SHA-256) with fail cooldown + configurable auto-lock
  • Balance screen: total USDC across chains + per-network breakdown
  • Send: paste / QR / on-device address book, Max amount, EIP-55 validation
  • Receive via EIP-681 QR; dedicated Bridge screen; per-network history; on-device contacts