> For the complete documentation index, see [llms.txt](https://docs.cotter.app/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.cotter.app/sdk-reference/flutter.md).

# Flutter

## Installation

Add Cotter to your `pubspec.yaml` , then run `flutter pub get`.

```yaml
dependencies:
  cotter:
```

Check the latest releases in [pub.dev](https://pub.dev/packages/cotter#-installing-tab-). You may need to restart your flutter for it to run pod install (stop flutter run and re run it).

#### For Android:

Update the `minSdkVersion` inside `android/app/build.gradle` to 18:

```yaml
defaultConfig {
    // TODO: Specify your own unique Application ID (https://developer.android.com/studio/build/application-id.html).
    applicationId "com.example.example"
    minSdkVersion 18   // 👈 Update this line
    targetSdkVersion 28
    versionCode flutterVersionCode.toInteger()
    versionName flutterVersionName
}
```

## **Complete Guides**

#### **Sign in with Device**

Allow users to login automatically from a device that they trust.

{% content-ref url="/pages/-M9angupK73fWUZjM7fe" %}
[Sign In with Device](/sdk-reference/flutter/sign-in-with-device.md)
{% endcontent-ref %}

#### Sign in with Email/Phone Number

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

{% content-ref url="/pages/-MATH96wMixRR82bWQJJ" %}
[Sign in with Email/Phone Number](/sdk-reference/flutter/sign-in-with-email-phone-number.md)
{% endcontent-ref %}

## Quickstart Guides

{% content-ref url="/pages/-M9aaGUmTZYju\_sjd17x" %}
[Flutter – Sign in with Device](/quickstart-guides/flutter-sign-in-with-device.md)
{% endcontent-ref %}