This page provides guidance on how to select the most suitable integration option(s) for your business.

Fourthline provides the following options:

Requirements

Before selecting an integration option, carefully define the scope and requirements for your use case(s).

We advise bringing together all relevant stakeholders, in particular your compliance team, to understand their needs and reach agreement.

Consider the following key questions:

• In which markets will you onboard new clients?
• What are the local compliance requirements in each market and how will you fulfill them?
• Do you want to use a mobile app or web browser?
• How much development effort do you want to invest in integration and maintenance?
• What level of flexibility and configurability do you require?
• What level of UI customizability do you want?
• How quickly do you want to launch?

Comparison

Compare the following factors across the different integration options:

Supported solutions

Explore which solutions and modules you can integrate with each integration option.

Supported solutions

The integration options support the following solutions and modules:

Solutions & modules	App Drop-in	Web SDK	App Components	API
Document Photo Document Liveness
Document NFC
Second ID Document
Selfie Photo Selfie Liveness
Digital Proof of Address Geolocation Physical Proof of Address
Client details Tax details
Qualified Electronic Signature
Bank Account Verification
AML Screening AML Monitoring
Client Authentication Document Authentication

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App Drop-in

Fourthline's App Drop-in provides data and image capture functionality for your Android or iOS mobile app. It is suitable for most business partners due to ease of integration, and low development and maintenance effort.

It takes care of all interaction with the client, collects the relevant data (e.g. ID document, selfie, geolocation), and uploads it to Fourthline for processing. You never handle sensitive personal data.

Fourthline provides the UI, which is built in line with industry-standard best practices for user experience (UX):

• The UI provides guidance to clients on how to complete their journey, real-time feedback, and image-quality detection to maximize conversion.
• You can localize the text and customize fonts and colors to match the look-and-feel of your brand.
• We continually update the UI to meet evolving regulatory requirements and market trends in interfaces and UX.

The user journey and flow of modules is orchestrated by the drop-in. We collect analytics data to continually improve conversion and UX.

The drop-in uses a streamlined API flow. You can also easily level up from single products to multi-product solutions with no additional API requests.

The API flow for a European Identity Verification is as follows:
Click to magnify

The drop-in specifications are as follows:

Fourthline also offers 3 cross-platform plugins:

• Cordova
• Flutter
• React Native

The plugins require the following additional modules:

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Web SDK

Fourthline's Web SDK smoothly redirects clients from your website (desktop or mobile) to a new browser window on their mobile device (hosted by Fourthline on a secure, private subdomain) via QR code or SMS. Alternatively, you can embed the SDK in your mobile site. It is suitable for most business partners due to ease of integration, and low development and maintenance effort.

Like the App Drop-in, the Web SDK provides data and image capture functionality and takes care of client interaction, orchestration, and analytics.

The Web SDK leverages our mobile-responsive, best-practice UI and you can customize the appearance to match the look-and-feel of your brand. You can also configure the language and level of formality before starting workflows or dynamically during flows.

Fourthline supports a wide range of browsers at the pace of vendor implementation of required APIs:

• At a high level, we support browsers that expose the following APIs: MediaDevices, MediaRecorder, and Geolocation.
• Browsers that aren't supported trigger an error at the start of the flow. The client can try a different browser without needing to restart the entire flow.

The API flow for a European Identity Verification is as follows:
Click to magnify

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App Components

App Components are standalone functionality modules for Android and iOS mobile apps. If you build custom user journeys, with your own UI, business logic, and orchestration, components reduce development time and effort. They capture images and data for you to upload via the API, leveraging Fourthline's data extraction AI services.

Fourthline provides the UI for the components, which you can customize in the same way as the App Drop-in. You can dynamically adjust functionality during flows, e.g. disable the tilted photo step.

This option is suitable if you want to build highly customized flows. It gives you a high level of control over your app implementations, but reduces development effort compared to API-only integration.

Some challenges you may encounter with Components implementations include conversion rates, version updates, maintenance, fraud detection, and complexity when introducing new products.

Fourthline also offers three cross-platform plugins:

• Cordova
• Flutter
• React Native

The plugins require the following additional modules:

The API flow for a European Identity Verification is as follows:
Click to magnify

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API only

With API-only integration, you capture and upload data and images, build your own UI, orchestrate the entire user journey, and implement analytics.

This option is suitable if you have an existing mobile app or website that you built and own, with no UI components from other vendors. It offers a very high level of customizability and configurability.

The API flow for a European Identity Verification is as follows:
Click to magnify

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