Yoti Doc Scan - Android SDK

Yoti is an identity checking platform that allows organisations to verify who people are, online and in person. The Yoti SDK, allows the user to take a photo of their ID, we then verify this instantly and prepare a response, which your system can then retrieve on your hosted site. Further information can be found here

Table of Contents

• Requirements
• Set up the SDK
  • R8 / Proguard
• Start the SDK
• Retrieve status of the session
  • Possible status for the session
• Customization
  • Font Colour
  • Colours
• Support
• License

Requirements

You have setup the Yoti Doc Scan SDK on your backend, you can find the documentation here

Minimum Android version supported: 21

Currently targeting Android version: 33

Note: we are using libraries from Android Jetpack. If you are still using the original Android Support Libraries you may encounter some issues when trying to use our SDK. We strongly recommend you to migrate your app to the new Androidx libraries: https://developer.android.com/jetpack/androidx/migrate

Setup the SDK

Make sure you have mavenCentral and microblink repository added in your allProjects entry in your root build.gradle:

allprojects {
    repositories {
        mavenCentral()
        maven { url 'https://maven.microblink.com' }
        maven { url "https://jitpack.io" }
        ...
    }
    ...
}

The Yoti SDK is composed of multiple feature modules. Each feature is optional, but you must include at least one to use the SDK.

The modules you include must match those requested by your backend. Attempts to use a module you haven't included will fail at runtime with a 600x response code.

Add modules you require to your build.gradle:

dependencies {
    //If you need document capture
    implementation 'com.yoti.mobile.android.sdk:yoti-sdk-doc-scan:3.5.0'
    //Or if you want the version without OCR and NFC capture, which is ~15Mb smaller in size
    implementation 'com.yoti.mobile.android.sdk:yoti-sdk-doc-scan-slim:3.5.0'

    //If you need supplementary documents
    implementation 'com.yoti.mobile.android.sdk:yoti-sdk-doc-scan-sup:3.5.0'

    //If you need liveness
    implementation 'com.yoti.mobile.android.sdk:yoti-sdk-liveness-zoom:3.5.0'

    //If you need selfie capture
    implementation 'com.yoti.mobile.android.sdk:yoti-sdk-facecapture:3.5.0'
    //Or if you want the version without an embedded AI model, which is ~20 MB smaller in size
    implementation 'com.yoti.mobile.android.sdk:yoti-sdk-facecapture-unbundled:3.5.0'
}

As you can see above, there are two options to add the doc-scan module to your app:

• yoti-sdk-doc-scan standard ID doc capture flow which uses automatic document capture via OCR and NFC capture for NFC-chip supported documents such as passports
• yoti-sdk-doc-scan-slim ID doc capture flow with a reduced feature set, using manual capture without OCR and NFC support. This results in a significantly smaller APK and install size.

There are also two options to add the facecapture module to your app:

• yoti-sdk-facecapture embeds an AI model for face detection.
• yoti-sdk-facecapture-unbundled will manage the download of the AI model via Google Play Services the first time you start using the AI model and thus is ~20 MB smaller in size. Additionally, you can add the following metadata to your AndroidManifest.xml to get the model downloaded as soon as the app is installed:

<application ...>
  ...
  <meta-data
      android:name="com.google.firebase.ml.vision.DEPENDENCIES"
      android:value="face" />

</application>

Also you will need to add the following to your app-level build.gradle file, inside your Android block:

    packagingOptions {
        exclude 'META-INF/*.kotlin_module'
        exclude "**/kotlin/**"
    }

    compileOptions {
        sourceCompatibility = '1.8'
        targetCompatibility = '1.8'
    }

And if you're using Firebase performance gradle Plugin, you'll need to disable it for debug build variant:

    android {
        ...
        buildTypes {
            ...
            debug {
                ...
                FirebasePerformance {
                    instrumentationEnabled false
                }
            }
         }
    }

To further decrease the size footprint of the SDK, you can also opt to manually exclude some of the educational videos shown in the verification flows:

• yds_aadhaar_educational (~750Kb) - only exclude if you do not support the Indian Aadhaar as a valid ID document type.
• yds_liveness_educational (~560Kb) - only exclude if you're using the yoti-sdk-liveness-zoom dependency.

Note: It's important to mention that excluding these resources is not recommended and should be only done in case the conditions described above apply to your use case. Otherwise, the user experience would be impacted on the related screens which will not be showing anything in place of the missing video resources.

To exclude these video resources during build time you have to:

1. Set shrinkResources true for your build type in your app build.gradle file. This should already be the case if you're concerned about app size.
2. Create a keep.xml file in your app module's res/raw resource directory, where you specify which resources you want to exclude:

<resources xmlns:tools="http://schemas.android.com/tools"
    tools:discard="@raw/yds_aadhaar_educational,@raw/yds_liveness_educational" />

For more information on resource shrinking and excluding resources, check out the official documentation.

R8 and Proguard

If you are using R8 the shrinking and obfuscation rules are included automatically.

ProGuard users must manually add the options from proguard-rules.pro. You might also need rules for retrofit, OkHttp, Okio and Gson which are dependencies of this library.

Start the SDK

After creating the session on your backend you will get a session ID and a session token, you will need to provide them to your app. Then you can start the SDK like this:

class MainActivity : AppCompatActivity() {

    private val yotiSdk = YotiSdk(this)

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)


        startButton.setOnClickListener {
            yotiSdk
                    .setSessionId("<Your Session ID>")
                    .setClientSessionToken("<Your Session Token>")
                    .start(this)
        }

    }
}

By default Activity request code is 9001 and you can handle it in onActivityResult by checking YOTI_SDK_REQUEST_CODE, but if you prefer to customise it, it is possible by specifying it in the start method:

            yotiSdk
                    .setSessionId("<Your Session ID>")
                    .setClientSessionToken("<Your Session Token>")
                    .start(this, <Your Request Code>)

Retrieve status of the session

Once the user completed the flow in the SDK, the user will be redirected to the Activity which started the SDK. You can then retrieve the current status of the current session like that:

class MainActivity : AppCompatActivity() {

    private val yotiSdk = YotiSdk(this)

    override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
        super.onActivityResult(requestCode, resultCode, data)
        if (requestCode == YOTI_SDK_REQUEST_CODE) {

            val sessionStatusCode = yotiSdk.sessionStatusCode
            val sessionStatusDescription = yotiSdk.sessionStatusDescription

            result_text.text = "Result code: $sessionStatusCode Message: $sessionStatusDescription"
        }
    }
}

Possible status for the session

Code	Message	Retry possible for the same session
0	Result with success	No
1000	No error occurred - the end-user cancelled the session for an unknown reason	Yes
2000	Unauthorised request (wrong or expired session token)	Yes
2001	Session not found	Yes
2003	SDK launched without session Token	Yes
2004	SDK launched without session ID	Yes
3000	Yoti's services are down or unable to process the request	Yes
3001	An error occurred during a network request	Yes
3002	User has no network	Yes
3003	A timeout occurred during a network request	Yes
4000	The user did not grant permissions to the camera	Yes
4001	User Wrong submission	Yes
5000	No camera (when user's camera was not found and file upload is not allowed)	No
5002	No more local tries for the liveness flow	Yes
5003	SDK is out-of-date - please update the SDK to the latest version	No
5004	Unexpected internal error	No
5005	Unexpected document scanning error	No
5006	Unexpected liveness error	No
5008	Unsupported configuration	No
5009	Storage Error: could not read/write on device app cache	No
6000	Document Capture dependency not found error	No
6001	Liveness Zoom dependency not found error	No
6002	Supplementary document dependency not found error	No
6003	Face Capture dependency not found error	No
7000	The user does not have the required documents to complete the session	No

Supported languages

Our SDK supports the 9 languages listed in the table below:

Language	Code
Arabic	ar
Dutch	nl
English (default)	en
French	fr
German	de
Italian	it
Russian	ru
Spanish	es
Turkish	tr

The default language we use is English, meaning that if your app supports any extra languages matching the one from the phone's settings, the SDK will fallback to English.

Since we also support Arabic, which is a right-to-left (RTL) language, you will need to add the android:supportsRtl="true" attribute to your application inside your AndroidManifest.xml file to ensure that the layout and text direction are correct, regardless of what languages your app supports.

If your app does not support one or more languages from the above table and the phone is set to such a language, in order to avoid situations where our SDK would be shown in a different language than the one your app is using, you need to declare the languages your app supports. You can achieve this by adding the following to your app/build.gradle file:

android {
    defaultConfig {
        resConfigs "en", "es", "it" // order does not matter, just add all your supported languages here
    }
}

Apart from helping you avoid issues such as the one outlined above, this will strip away all language related resources except for those in the specified list. Thus, you avoid resource contamination and it makes your app smaller in size.

Customisation

You can customise the appearance of the screens of the SDK by overriding some of the colours.

Font type

In order to change the font type you need to:

1. Add your own font type .tff files to res/font, 3 files in total for bold, regular and medium
2. Declare three resource items of type font (which will override the ones declared in the SDK):

<item name="yoti_sdk_fontStyleBold" type="font">@font/your-font-bold</item>
<item name="yoti_sdk_fontStyleRegular" type="font">@font/your-font-regular</item>
<item name="yoti_sdk_fontStyleMedium" type="font">>@font/your-font-medium</item>

Font Colour

In order to change the font colour you just need to override the following colour:

<color name="yoti_sdk_colorFont">

Colours

In order to change the colours of the different elements of the screens you just need to declare the following colours:

• For the main app branding colour:

<color name="yoti_sdk_colorPrimary">

• For the darker variant:

<color name="yoti_sdk_colorPrimaryDark">

• For the UI controls like checkboxes and text fields:

<color name="yoti_sdk_colorAccent">
<color name="yoti_sdk_colorAccentPressed">#AA164A</color>
<color name="yoti_sdk_colorAccentDisabled">#F8B3CB</color>

Reducing the size of your APK

We recommend that you distribute your app using App Bundle. This new Google Play feature allows you to use Play Feature delivery which uses advanced capabilities of app bundles, allowing certain features of your app to be delivered conditionally or downloaded on demand. App Bundle also defer apk generation to Google Play, allowing it to generate minimal APK for each specific device that downloads your app, including only required processor architecture support.

Also, don't forget to shrink, obfuscate and optimize your app.

Troubleshooting

If you are using the yoti-sdk-liveness-zoom module together with the App Bundle publishing format, you might encounter the following runtime exception when attempting to open the scan screen:

Native library failed to load: null

This is caused by a third party library we use. To fix it, you can try adding the following to your build.gradle file:

android {
    packagingOptions {
        jniLibs {
            useLegacyPackaging = true
        }
    }
}

Support

If you have any other questions please do not hesitate to contact clientsupport@yoti.com. Once we have answered your question we may contact you again to discuss Yoti products and services. If you'd prefer us not to do this, please let us know when you e-mail.

License

Yoti Doc Scan Android SDK is under a Proprietary License see this link for more information

We also list all open-source licensed software that has been incorporated into the SDK on files inside .aar.

• res/raw/yds_identity_verification_licenses_core.json
• res/raw/yds_identity_verification_licenses_id_document.json
• res/raw/yds_identity_verification_licenses_supplementary_document.json