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

# Authentication screens

<Warning>
  **Step-up authentication** and **device registration** are required
  for all headless integrations. Without these, users will be blocked
  during login or sensitive actions. See the
  [2026\_04\_01 upgrade guide](/overview/migrations/api/2026_04_01).
</Warning>

Implement the screens below based on which authentication methods you've
enabled in your [dashboard](https://app.dynamic.xyz/dashboard). Email
is enabled by default for most projects.

## Screens

| Authentication method  | Description                                        | Guide                                                                  |
| ---------------------- | -------------------------------------------------- | ---------------------------------------------------------------------- |
| Email                  | Collect email, send OTP, verify code               | [Guide](/flutter/authentication)                                       |
| SMS                    | Collect phone number, send OTP, verify code        | [Guide](/flutter/authentication)                                       |
| Social                 | Trigger OAuth redirect per provider                | [Guide](/flutter/social-authentication)                                |
| External JWT           | Sign in with an externally issued JWT (enterprise) | [Guide](/flutter/authentication#external-jwt-authentication)           |
| Passkey                | Authenticate with a registered passkey             | [SDK Reference](/flutter/sdk-reference/overview#passkeys-sdk-passkeys) |
| MFA                    | Prompt for TOTP code or passkey                    | [SDK Reference](/flutter/sdk-reference/overview#mfa-sdk-mfa)           |
| Step-up authentication | Re-verify identity before sensitive actions        | [Guide](/flutter/authentication-methods/step-up-auth/overview)         |
| Device registration    | Verify identity on unrecognized device login       | [Guide](/flutter/authentication-methods/device-registration)           |