# Web

## Complete Guides

#### Sign in with Email/Phone Number

Authenticate users by sending a Magic Link or OTP via email, SMS, or WhatsApp

{% content-ref url="web/web-sdk-verify-email-phone" %}
[web-sdk-verify-email-phone](https://docs.cotter.app/sdk-reference/web/web-sdk-verify-email-phone)
{% endcontent-ref %}

#### Sign in with WebAuthn

Authenticate users using TouchID or Windows Hello from your website.

{% content-ref url="web/sign-in-with-webauthn" %}
[sign-in-with-webauthn](https://docs.cotter.app/sdk-reference/web/sign-in-with-webauthn)
{% endcontent-ref %}

#### Sign in with Device

If you have **mobile app**, you can ask the user to approve the login request from their phone.

{% content-ref url="web/web-sdk-passwordless-login" %}
[web-sdk-passwordless-login](https://docs.cotter.app/sdk-reference/web/web-sdk-passwordless-login)
{% endcontent-ref %}

## Quickstart Guides

{% content-ref url="../quickstart-guides/react-magic-link-with-email-and-phone" %}
[react-magic-link-with-email-and-phone](https://docs.cotter.app/quickstart-guides/react-magic-link-with-email-and-phone)
{% endcontent-ref %}

{% content-ref url="../quickstart-guides/html-magic-link-with-email-and-phone" %}
[html-magic-link-with-email-and-phone](https://docs.cotter.app/quickstart-guides/html-magic-link-with-email-and-phone)
{% endcontent-ref %}

{% content-ref url="../quickstart-guides/react-webauthn" %}
[react-webauthn](https://docs.cotter.app/quickstart-guides/react-webauthn)
{% endcontent-ref %}