Android Integration

1. Install the SDK#

Add the dependency to your app-level build.gradle:

dependencies {
    implementation("org.very:sdk:1.0.64")
}

2. Configure your app#

Add permissions to AndroidManifest.xml:

<uses-permission android:name="android.permission.CAMERA" />
<uses-permission android:name="android.permission.INTERNET" />

3. Enroll a new user#

Pass null for userId to register a new user. The SDK opens a consent screen, then guides the user through a palm scan.

import org.very.sdk.VerySDK
import org.very.sdk.VeryConfig
import org.very.sdk.VeryResult
import org.very.sdk.VeryPresentationStyle

// Check device support first
if (!VerySDK.isSupported(context)) {
    Log.w("Very", "Device not supported")
    return
}

val config = VeryConfig(
    sdkKey = "your_sdk_key",       // from Developer Portal
    userId = null,                  // null = new enrollment
    clientReferenceId = "gate-withdrawal-42", // your transaction/session ID
    themeMode = "dark"              // "dark" or "light"
)

VerySDK.authenticate(
    context = this,
    config = config,
    presentationStyle = VeryPresentationStyle.FULL_SCREEN
) { result: VeryResult ->
    if (result.isSuccess) {
        Log.d("Very", "User ID: ${result.userId}")
        Log.d("Very", "User status: ${result.userStatus}")
        Log.d("Very", "Signed token: ${result.signedToken}")
    } else {
        Log.e("Very", "Error: ${result.errorType} — ${result.errorMessage}")
    }
}

4. Verify an existing user#

Pass the user's ID from a previous enrollment to verify their identity.

val config = VeryConfig(
    sdkKey = "your_sdk_key",
    userId = "vu-1ed0a927-...",    // existing user's ID from previous enrollment
    themeMode = "dark"
)

VerySDK.authenticate(
    context = this,
    config = config,
    presentationStyle = VeryPresentationStyle.FULL_SCREEN
) { result: VeryResult ->
    if (result.isSuccess) {
        Log.d("Very", "Verified user: ${result.userId}")
        Log.d("Very", "Signed token: ${result.signedToken}")
    } else {
        Log.e("Very", "Error: ${result.errorType} — ${result.errorMessage}")
    }
}

5. Verify the signed token (backend)#

When authentication succeeds, the SDK returns userId and signedToken. Send signedToken to your backend:

POST /api/verify-palm
Content-Type: application/json

{
  "signedToken": "eyJhbGciOiJFZERTQSIsImtpZCI6..."
}

Follow the secure backend verification example to validate the EdDSA signature, key ID, issuer, app audience, time window, action, session and token IDs, and expected user. After all checks pass, trust sub as the user's VeryAI ID:

{
  "iss": "https://api.very.org",
  "sub": "vu-1ed0a927-a336-45dd-9c73-20092db9ae8d",
  "aud": "your_app_id",
  "act": "verify",
  "sid": "sdk_session_id",
  "jti": "34fa6d08-28d4-4a29-85f8-5064ea8ae32e",
  "exp": 1761010175,
  "iat": 1761009875
}

• For enrollment: store the sub (user ID) - use it for future verifications
• For verification: confirm the sub matches the expected user
• code is an SDK status string, not an OAuth authorization code

VeryConfig#

Parameter	Type	Description
sdkKey	String	Your SDK API key from the Developer Portal
userId	String?	null for enrollment, user ID for verification
clientReferenceId	String?	Your transaction or session ID (up to 255 characters), included in webhook events for the review started by this SDK call
language	String?	BCP 47 locale code (e.g. "en", "es", "en-IN", "zh-HK") — see supported languages. Defaults to device language.
themeMode	String	"dark" (default) or "light"
customStrings	Map<String, String>?	Override the palm-scan status copy, keyed by VeryCustomString. See Custom strings.

Custom strings#

Override the palm-scan status copy with customStrings, keyed by the stable VeryCustomString constants. A caller-supplied value takes priority over the SDK's built-in localized string; blank values and unknown keys fall back to the localized default. The SDK renders your value verbatim, so pass already-localized text.

import org.very.sdk.VeryCustomString

// Override the palm-scan status copy. A caller value wins over the
// built-in localized string; blank values and unknown keys fall back
// to the localized default. Pass your own already-localized text.
val config = VeryConfig(
    sdkKey = "your_sdk_key",
    userId = null,
    customStrings = mapOf(
        VeryCustomString.SHOW_YOUR_HAND       to "Hold up your palm",
        VeryCustomString.SHOW_YOUR_FIRST_HAND to "Hold up your first palm",
        VeryCustomString.CONNECT_DOTS         to "Connect the dots",
    )
)

Key	Default text	Where it shows
VeryCustomString.SHOW_YOUR_HAND	Show your hand	Default scan-page status
VeryCustomString.SHOW_YOUR_FIRST_HAND	Show your first hand	Scan-page status during first-time enrollment
VeryCustomString.CONNECT_DOTS	Connect the dots	"Connect the dots" gesture prompt

VeryResult#

Property	Type	Description
isSuccess	Boolean	true if authentication completed successfully
code	String	SDK status string, not an OAuth authorization code
userId	String	The user's app-scoped VeryAI ID
signedToken	String?	Ed25519-signed JWT for backend verification
userStatus	String?	Consolidated status. pending is a successful submission awaiting review.
errorType	VeryErrorType?	Typed error code (see Error Handling)
errorMessage	String?	Human-readable error message

Presentation styles#

• FULL_SCREEN — full-screen activity (default)
• BOTTOM_SHEET — bottom sheet dialog