DiditSDK for Flutter

A Flutter plugin for Didit Identity Verification. Wraps the native iOS and Android SDKs with a unified Dart API for document scanning, NFC passport reading, face verification, and liveness detection.

Requirements

Requirement	Minimum Version
Flutter	3.3+
Dart	3.11+
iOS	13.0+ (NFC requires iOS 15.0+)
Android	API 23+ (6.0 Marshmallow)

Installation

Add the dependency to your pubspec.yaml:

dependencies:
  didit_sdk: ^3.2.0

Then run:

flutter pub get

iOS Setup

Add the DiditSDK podspec to your ios/Podfile (it's not on CocoaPods trunk):

# Inside your target block:
pod 'DiditSDK', :podspec => 'https://raw.githubusercontent.com/didit-protocol/sdk-ios/main/DiditSDK.podspec'

Then install dependencies:

cd ios
pod install

Android Setup

Add the following packaging rule to your android/app/build.gradle.kts inside the android block:

android {
    packaging {
        resources {
            pickFirsts += "META-INF/versions/9/OSGI-INF/MANIFEST.MF"
        }
    }
}

This resolves a duplicate metadata file shipped by the SDK's cryptography dependencies (BouncyCastle). Without it the build will fail with a mergeDebugJavaResource error.

Permissions

iOS

Add the following keys to your app's Info.plist:

Permission	Info.plist Key	Description	Required
Camera	NSCameraUsageDescription	Document scanning and face verification	Yes
NFC	NFCReaderUsageDescription	Read NFC chips in passports/ID cards	If using NFC
Location	NSLocationWhenInUseUsageDescription	Geolocation for fraud prevention	Optional

<key>NSCameraUsageDescription</key>
<string>Camera access is required for identity verification.</string>
<key>NFCReaderUsageDescription</key>
<string>NFC is used to read passport chip data for identity verification.</string>
<key>NSLocationWhenInUseUsageDescription</key>
<string>Location access is used to detect your country for identity verification.</string>

NFC Configuration (for passport/ID chip reading)

1. Add NFC Capability in Xcode:

   • Select your target > Signing & Capabilities > + Capability > Near Field Communication Tag Reading

2. Add ISO7816 Identifiers to Info.plist:

   <key>com.apple.developer.nfc.readersession.iso7816.select-identifiers</key>
   <array>
       <string>A0000002471001</string>
   </array>
   

Android

The following permissions are declared in the native SDK's AndroidManifest.xml and merged automatically:

Permission	Description	Required
INTERNET	Network access for API communication	Yes
ACCESS_NETWORK_STATE	Detect network availability	Yes
CAMERA	Document scanning and face verification	Yes
NFC	Read NFC chips in passports/ID cards	If using NFC

Camera and NFC hardware features are declared as optional (android:required="false"), so your app can be installed on devices without these features.

Quick Start

import 'package:didit_sdk/sdk_flutter.dart';

final result = await DiditSdk.startVerification('your-session-token');

switch (result) {
  case VerificationCompleted(:final session):
    print('Status: ${session.status}');
    print('Session ID: ${session.sessionId}');
  case VerificationCancelled():
    print('User cancelled');
  case VerificationFailed(:final error):
    print('Error: ${error.type} - ${error.message}');
}

Integration Methods

The SDK supports two integration methods:

Method 1: Session Token (Recommended for Production)

Create a session on your backend using the Create Verification Session API, then pass the token to the SDK:

// Your backend creates a session and returns the token
final sessionToken = await yourBackend.createVerificationSession(userId);

// Pass the token to the SDK
final result = await DiditSdk.startVerification(sessionToken);

This approach gives you full control over:

• Associating sessions with your users (vendor_data)
• Setting custom metadata
• Configuring callbacks per session

Method 2: Workflow ID (Simpler Integration)

For simpler integrations, the SDK can create sessions directly using your workflow ID:

final result = await DiditSdk.startVerificationWithWorkflow(
  'your-workflow-id',
  vendorData: 'user-123',
  contactDetails: ContactDetails(email: 'user@example.com'),
  config: DiditConfig(loggingEnabled: true),
);

Configuration

Customize the SDK behavior by passing a DiditConfig object:

final result = await DiditSdk.startVerification(
  'your-session-token',
  config: DiditConfig(
    languageCode: 'es',       // Force Spanish language
    fontFamily: 'Avenir',     // Custom font
    loggingEnabled: true,     // Debug logging
  ),
);

Configuration Options

Option	Type	Default	Description
languageCode	String?	Device locale	ISO 639-1 language code (e.g. "en", "fr", "ar")
fontFamily	String?	System font	Custom font family name
loggingEnabled	bool	false	Enable SDK debug logging

All fields are optional. If no config is provided, the SDK uses sensible defaults.

languageCode

Sets the language for the entire verification UI. Pass an ISO 639-1 code (e.g. "en", "fr", "es", "ar"). If not set, the SDK automatically detects the device locale and falls back to English.

// Force French
await DiditSdk.startVerification(token, config: DiditConfig(languageCode: 'fr'));

// Use device locale (default)
await DiditSdk.startVerification(token);

fontFamily

Overrides the font used throughout the SDK UI. The font must be registered in your app's native configuration:

• iOS: Add the font file to your Xcode project and list it in Info.plist under UIAppFonts.
• Android: Place the font file in android/app/src/main/res/font/.

await DiditSdk.startVerification(token, config: DiditConfig(fontFamily: 'Avenir'));

loggingEnabled

Enables verbose debug logging from the native SDK. Useful during development to inspect the SDK's internal state, API calls, and error details. Should be disabled in production.

await DiditSdk.startVerification(token, config: DiditConfig(loggingEnabled: true));

Language Support

The SDK supports 40+ languages. If no language is specified, the SDK uses the device locale with English as fallback.

Supported Languages

Language	Code	Language	Code
English	en	Korean	ko
Arabic	ar	Lithuanian	lt
Bulgarian	bg	Latvian	lv
Bengali	bn	Macedonian	mk
Catalan	ca	Malay	ms
Czech	cs	Dutch	nl
Danish	da	Norwegian	no
German	de	Polish	pl
Greek	el	Portuguese	pt
Spanish	es	Portuguese (Brazil)	pt-BR
Estonian	et	Romanian	ro
Persian	fa	Russian	ru
Finnish	fi	Slovak	sk
French	fr	Slovenian	sl
Hebrew	he	Serbian	sr
Hindi	hi	Swedish	sv
Croatian	hr	Thai	th
Hungarian	hu	Turkish	tr
Armenian	hy	Ukrainian	uk
Indonesian	id	Uzbek	uz
Italian	it	Vietnamese	vi
Japanese	ja	Chinese (Simplified)	zh
Georgian	ka	Chinese (Traditional)	zh-TW
Montenegrin	cnr	Somali	so

Advanced Options

These options are only available with startVerificationWithWorkflow, where the SDK creates the session on your behalf.

Contact Details (Prefill & Notifications)

Provide contact details to prefill verification forms and enable email notifications:

final result = await DiditSdk.startVerificationWithWorkflow(
  'your-workflow-id',
  contactDetails: ContactDetails(
    email: 'user@example.com',
    sendNotificationEmails: true,
    emailLang: 'en',
    phone: '+14155552671',
  ),
);

Field	Type	Description
email	String?	Email address for verification notifications
sendNotificationEmails	bool?	Whether to send status update emails
emailLang	String?	ISO 639-1 language code for notification emails
phone	String?	Phone number in E.164 format (e.g. "+14155552671")

Expected Details (Cross-Validation)

Provide expected user details for automatic cross-validation with extracted document data:

final result = await DiditSdk.startVerificationWithWorkflow(
  'your-workflow-id',
  expectedDetails: ExpectedDetails(
    firstName: 'John',
    lastName: 'Doe',
    dateOfBirth: '1990-05-15',
    nationality: 'USA',
    country: 'USA',
  ),
);

Field	Type	Format	Description
firstName	String?	—	Expected first name
lastName	String?	—	Expected last name
dateOfBirth	String?	YYYY-MM-DD	Expected date of birth
gender	String?	—	Expected gender
nationality	String?	ISO 3166-1 alpha-3	Expected nationality (e.g. "USA", "GBR")
country	String?	ISO 3166-1 alpha-3	Expected country of residence
address	String?	—	Expected address
identificationNumber	String?	—	Expected document ID number
ipAddress	String?	—	Expected IP address
portraitImage	String?	—	Base64-encoded portrait image for face comparison

All fields are optional.

Custom Metadata

Store custom JSON metadata with the session (not displayed to user):

final result = await DiditSdk.startVerificationWithWorkflow(
  'your-workflow-id',
  vendorData: 'user-123',
  metadata: '{"internalId": "abc123", "source": "mobile-app"}',
);

Verification Results

Both startVerification and startVerificationWithWorkflow return a Future<VerificationResult>. The result is a sealed class — use pattern matching to determine the outcome.

Result Types

Type	Description	Fields
VerificationCompleted	Verification flow completed	session (always present)
VerificationCancelled	User cancelled the flow	session (optional)
VerificationFailed	An error occurred	error (always present), session (optional)

SessionData

Property	Type	Description
sessionId	String	The unique session identifier
status	VerificationStatus	approved, pending, or declined

VerificationError

Property	Type	Description
type	VerificationErrorType	Error category (see table below)
message	String	Human-readable error description

Error Types

Error Type	Description
sessionExpired	The session has expired
networkError	Network connectivity issue
cameraAccessDenied	Camera permission not granted
notInitialized	SDK not initialized (Android only)
apiError	API request failed
unknown	Other error with message

Complete Result Handling Example

import 'package:didit_sdk/sdk_flutter.dart';

Future<void> verify(String token) async {
  final result = await DiditSdk.startVerification(token);

  switch (result) {
    case VerificationCompleted(:final session):
      switch (session.status) {
        case VerificationStatus.approved:
          print('Approved! Session: ${session.sessionId}');
          // User is verified — grant access
        case VerificationStatus.pending:
          print('Under review. Session: ${session.sessionId}');
          // Show "verification in progress" UI
        case VerificationStatus.declined:
          print('Declined. Session: ${session.sessionId}');
          // Handle declined verification
      }

    case VerificationCancelled(:final session):
      print('User cancelled.');
      if (session != null) {
        print('Session: ${session.sessionId}');
      }
      // Maybe show retry option

    case VerificationFailed(:final error):
      print('Error [${error.type}]: ${error.message}');
      // Handle error — show retry or contact support
  }
}

API Reference

DiditSdk.startVerification(token, {config})

Start verification with an existing session token.

Parameter	Type	Required	Description
token	String	Yes	Session token from the Didit API
config	DiditConfig?	No	SDK configuration options

Returns: Future<VerificationResult>

DiditSdk.startVerificationWithWorkflow(workflowId, {...})

Start verification by creating a new session with a workflow ID.

Parameter	Type	Required	Description
workflowId	String	Yes	Workflow ID that defines verification steps
vendorData	String?	No	Your user identifier or reference
metadata	String?	No	Custom JSON metadata for the session
contactDetails	ContactDetails?	No	Prefill contact information
expectedDetails	ExpectedDetails?	No	Expected identity details for cross-validation
config	DiditConfig?	No	SDK configuration options

Returns: Future<VerificationResult>

Running the Example App

The repository includes a fully functional example app.

iOS

cd example
flutter pub get
cd ios && pod install && cd ..
flutter run

To run on a real device, open example/ios/Runner.xcworkspace in Xcode, configure your signing team, and select your device.

Android

cd example
flutter pub get
flutter run

License

Copyright (c) 2026 Didit. All rights reserved.