> ## Documentation Index
> Fetch the complete documentation index at: https://docs.lab4pay.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Integration Overview

> **Choose the right integration method for your use case.** Pay-Connect offers two distinct approaches to meet different technical requirements and deployment scenarios.

<Columns cols={2}>
  <Card title="API Integration" icon="sparkles" href="#api-integration">
    Best for backend-driven systems and advanced POS platforms requiring full control over payment workflows.
  </Card>

  <Card title="App2App Integration" icon="sparkles" href="#app2app-integration">
    Direct device-to-device communication for lightweight Android POS applications with no backend dependency.
  </Card>
</Columns>

## API Integration

API Integration is designed for backend-driven systems and advanced POS platforms that require full control over payment workflows.

<Accordion title="Key characteristics" iconType="regular">
  * **Centralized terminal management** – Manage multiple terminals from a single backend
  * **Full transaction lifecycle control** – Complete control over all payment operations
  * **Configuration and metadata support** – Customize terminal settings and add transaction metadata
  * **Asynchronous updates via webhooks** – Real-time notifications for transaction events
</Accordion>

<Info>
  **Best for:** Enterprise systems, multi-location businesses, and applications requiring comprehensive payment management.
</Info>

## App2App Integration

App2App Integration enables direct communication between applications running on the same device or network.

<Accordion title="Key characteristics">
  * **Lightweight integration** – Minimal setup and configuration required
  * **No backend dependency** – Fully operates on the device without server infrastructure
  * **Ideal for Android POS applications** – Native Android-to-Android communication
  * **Core payment operations** – Focused on essential transaction functions
</Accordion>

<Info>
  **Best for:** Small businesses, mobile POS solutions, and applications with simple payment needs.
</Info>

## Feature comparison

Compare the capabilities of each integration method to determine which best fits your requirements:

| Feature                    | API Integration | App2App Integration |
| -------------------------- | --------------- | ------------------- |
| Terminal pairing           | ✅               | ✅                   |
| Charge                     | ✅               | ✅                   |
| Cancel                     | ✅               | ✅                   |
| Revert                     | ✅               | ✅                   |
| Refund                     | ✅               | ✅                   |
| Independent refund         | ✅               | ✅                   |
| Configuration              | ✅               | ❌                   |
| Transaction patch          | ✅               | ❌                   |
| Transaction status polling | ✅               | ❌                   |
| Webhooks                   | ✅               | ❌                   |