> ## Documentation Index
> Fetch the complete documentation index at: https://docs.crossmint.com/llms.txt
> Use this file to discover all available pages before exploring further.

# useSigner

> Kotlin Function

**Function**

```kotlin theme={null}
suspend fun EVMWallet.useSigner(signer: DelegatedSigner.Passkey, credentialManager: CredentialManager, activityProvider: () -> Activity, rpId: String = DEFAULT_PASSKEY_RP_ID): Result<Unit, WalletError>
```

Activates a passkey signer on this wallet using Android CredentialManager.