> ## Documentation Index
> Fetch the complete documentation index at: https://docs.verisoul.ai/llms.txt
> Use this file to discover all available pages before exploring further.
# Flutter
> Integrating Verisoul in Flutter Apps
*To run the SDK a Verisoul Project ID is required.* Schedule a call [here](https://meetings.hubspot.com/henry-legard) to get started.
## System Requirements
* Flutter SDK 3.0 or higher
* Dart 2.17 or higher
* iOS 14.0 or higher
* Android API level 24 (Android 7.0) or higher
* For Web: Modern browsers with JavaScript enabled
* SDK Size: \~120 KB (plus native iOS and Android SDK dependencies)
## Installation
### Add Dependency
```yaml theme={null}
dependencies:
flutter:
sdk: flutter
# ...
verisoul_sdk: 0.4.65
```
### Android Configuration
#### 1. Update Minimum SDK Version
Update the Android minimum `minSdk` to **24** in `android/app/build.gradle`:
```groovy theme={null}
defaultConfig {
minSdk = 24
//...
}
```
#### 2. Add Maven Repository
If an exception occurs during the build stating that the `ai.verisoul:android` package cannot be downloaded, add the following Maven repository inside your `android/build.gradle` file:
```groovy theme={null}
allprojects {
repositories {
// ...
maven { url = uri("https://us-central1-maven.pkg.dev/verisoul/android") }
}
}
```
### iOS Configuration
For iOS-specific configuration including Device Check and App Attest setup, please refer to the [iOS SDK Documentation](/integration/frontend/ios#ios-device-check).
## Usage
### Initialize the SDK
Call `configure()` when your application starts, before running your app:
```dart theme={null}
import 'package:verisoul_sdk/verisoul.dart';
void main() {
WidgetsFlutterBinding.ensureInitialized();
VerisoulSdk.configure(projectId: "Project ID ", environment: VerisoulEnvironment.prod);
runApp(const MyApp());
}
```
The `configure()` method initializes the Verisoul SDK with your project credentials. This method must be called once when your application starts.
**Parameters:**
* `projectId`: Your unique Verisoul project identifier
* `environment`: The environment to use `VerisoulEnvironment.prod` for production or `VerisoulEnvironment.sandbox` for testing
### Get Session ID
The `getSessionApi()` method returns the current session identifier after the SDK has collected sufficient device data. This session ID is required to request a risk assessment from Verisoul's API.
**Important Notes:**
* Session IDs are short-lived and expire after 24 hours
* The session ID becomes available once minimum data collection is complete (typically within seconds)
* You should send this session ID to your backend, which can then call Verisoul's API to get a risk assessment
**Example:**
```dart theme={null}
final session = await VerisoulSdk.getSessionApi();
```
### Provide Touch Events
Wrap your App with `VerisoulWrapper` to automatically capture touch events:
```dart theme={null}
runApp(VerisoulWrapper(child: const MyApp()));
```
## Web Support
### Add Verisoul Script
Add the Verisoul script to your `web/index.html`:
```html theme={null}
```
**Replace the following parameters:**
* **`{env}`**: Use either `prod` or `sandbox`
* **`{project_id}`**: Your project ID, which must match the environment
### Content Security Policy (CSP)
If your application has a Content Security Policy, update it to include the following Verisoul domains:
```html theme={null}
```
### Set Account Data (Web Only)
The `setAccountData()` function provides a simplified way to send user account information to Verisoul directly from the client side. While easy to integrate, this method has important limitations:
* **Offline analysis only**: Data sent via account() is only visible in the Verisoul dashboard
* **No real-time decisions**: Unlike the server-side API, this method doesn't allow your application to receive and act on Verisoul's risk scores in real-time
* **Limited use case**: Designed specifically for initial pilots and evaluation purposes
```dart theme={null}
await VerisoulSdk.setAccountData(
id: "example-id",
email: "example@example.com",
metadata: {"paid": true}
);
```
### Error Codes
The SDK throws `VerisoulException` with the following error codes:
| Error Code | Description | Recommended Action |
| -------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------- |
| INVALID\_ENVIRONMENT | The environment parameter passed to `Verisoul.configure()` is invalid. Valid values are "dev", "sandbox", or "prod". | Ensure the environment parameter is exactly "dev", "sandbox", or "prod" (case-sensitive, no whitespace). |
| SESSION\_UNAVAILABLE | A valid session ID could not be obtained. This typically occurs when Verisoul's servers are unreachable due to network blocking or a very slow connection. | Implement exponential backoff. Prompt user to check network or disable network blocker. |
| WEBVIEW\_UNAVAILABLE | WebView is not available on the device. This can occur when WebView is disabled, missing, uninstalled, or corrupted on the device. | Prompt user to enable WebView in settings, update Android System WebView, or switch devices. |
| WEBVIEW\_RENDERER\_CRASHED | The WebView renderer process crashed, typically due to low memory or resource pressure. | Retry the request (SDK will attempt recovery), encourage users to update Android System WebView, or switch devices. |
#### Exception Structure
All errors are thrown as `VerisoulException` with the following properties:
| Property | Type | Description |
| -------- | ---------- | ------------------------------------------------------- |
| code | String | One of the error codes above |
| message | String | Human-readable error description |
| cause | Throwable? | The underlying exception that caused the error (if any) |
## Example
For a complete working example, see the [Flutter Sample App](/examples/flutter-sample-app).
## Additional Resources
* [Verisoul Flutter SDK on Pub.dev](https://pub.dev/packages/verisoul_sdk)