# Quickstart Guides

- [All Guides & Tutorials](https://docs.cotter.app/quickstart-guides/all-guides-and-tutorials.md)
- [HTML – Sign in with Email/Phone](https://docs.cotter.app/quickstart-guides/html-magic-link-with-email-and-phone.md): Easily add email and phone number verification using Cotter's SDK. Send a magic link to your users via email, SMS or WhatsApp in just a few lines of code.
- [React – Sign in with Email/Phone](https://docs.cotter.app/quickstart-guides/react-magic-link-with-email-and-phone.md): Easily add email and phone number verification using Cotter's SDK. Send a magic link to your users via email, SMS or WhatsApp in just a few lines of code.
- [React – WebAuthn](https://docs.cotter.app/quickstart-guides/react-webauthn.md): Sign in users faster using WebAuthn: sign in with TouchID or Windows Hello from a web browser.
- [React Native – Sign in with Device](https://docs.cotter.app/quickstart-guides/react-native-quickstart.md): Cotter's Passwordless SDK authenticates your user based on their device. It allows a seamless, fast, and secure way for your user to login to your React Native App.
- [iOS – Sign in with Device](https://docs.cotter.app/quickstart-guides/ios-quickstart.md): Cotter's Passwordless SDK authenticates your user using the FIDO protocol. It allows a seamless, fast, and secure way for your user to login to your iOS App. Authenticate your users in 4 simple steps:
- [Flutter – Sign in with Device](https://docs.cotter.app/quickstart-guides/flutter-sign-in-with-device.md): Cotter's Passwordless SDK authenticates your user based on their device. It allows a seamless, fast, and secure way for your user to login to your React Native App.


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Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://docs.cotter.app/quickstart-guides.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.