# Enable session replay on Android

## Overview

Follow this guide to enable Session Replay for [Real User Monitoring (RUM)](https://coralogix.com/docs/user-guides/rum/getting-started/real-user-monitoring/index.md) in your Android app.

[Session Replay](https://coralogix.com/docs/user-guides/rum/product-features/session-replay/index.md) captures a visual sequence of user interactions in your app by recording periodic screenshots. This allows you to analyze what the user saw before, during, and after an issue — helping you quickly pinpoint the source of errors, performance slowdowns, or unexpected behavior. Use Session Replay to recreate the user experience and better understand the context behind each session.

## Prerequisites

Before enabling Session Replay, you must install and initialize the [Coralogix Android RUM SDK](https://coralogix.com/docs/user-guides/rum/sdk-installation/android/index.md) in your app.

Note

The Session Replay feature extends the Android RUM SDK and must be initialized **after** the base SDK setup. Attempting to initialize Session Replay without the base SDK will result in an initialization error.

## Session Replay by default

Session Replay on Android:

- Evaluates UI one frame per second (FPS) and captures only if the layout changed since the previous screenshot.
- Masks all text inputs (when `maskAllTexts` is enabled).
- Redacts sensitive input field types (passwords, emails, numbers, etc.) if specified.
- Samples 100% of sessions by default.

You can customize these defaults using the configuration options below.

## Configure and initialize

Use the `SessionReplayOptions` class to configure capture behavior, privacy masking, and sampling.

### Example

```kotlin
import android.app.Application
import com.coralogix.android.sdk.session_replay.SessionReplay
import com.coralogix.android.sdk.session_replay.model.SessionReplayOptions
import com.coralogix.android.sdk.internal.infrastructure.display.enums.EditTextType

class MyApp : Application() {
    override fun onCreate() {
        super.onCreate()
        val options = SessionReplayOptions(
            captureScale = 0.5f, // Scale screenshots to half resolution
            captureCompressQuality = 0.8f, // Compress images for size optimization
            sessionRecordingSampleRate = 80, // Capture 80% of sessions
            autoStartSessionRecording = true, // Start recording automatically
            maskAllTexts = false, // Do not mask all text by default
            maskInputFieldsOfTypes = listOf(
                EditTextType.PASSWORD,
                EditTextType.EMAIL
            )
        )
        SessionReplay.initialize(this, options)
    }
}
```

## Options reference

Configuration fields for `SessionReplayOptions`:

| Option                       | Type                 | Description                                                                            | Default       |
| ---------------------------- | -------------------- | -------------------------------------------------------------------------------------- | ------------- |
| `autoStartSessionRecording`  | `Boolean`            | Start recording automatically                                                          | `true`        |
| `captureScale`               | `Float`              | Screenshot resolution scale factor (0–1). Lower values reduce size and memory usage    | `0.5f`        |
| `captureCompressQuality`     | `Float`              | Image compression (0–1). Lower values reduce fidelity and file size                    | `1.0f`        |
| `sessionRecordingSampleRate` | `Int` (0–100)        | % of sessions to capture                                                               | `100`         |
| `maskAllTexts`               | `Boolean`            | Redact all on-screen text                                                              | `true`        |
| `maskInputFieldsOfTypes`     | `List<EditTextType>` | Redact only specific input fields (e.g., password, email, phone)                       | `emptyList()` |
| `maskAllImages`              | `Boolean`            | Mask all images in captured views                                                      | `false`       |
| `textsToMask`                | `List<String>`       | Text patterns to redact (supports regex). Applied when `maskAllTexts` is `false`       | `emptyList()` |
| `sampleFrameRatePerSecond`   | `Int`                | How frequently the SDK evaluates the layout for changes. Lower values reduce CPU usage | `1`           |

## Image capture triggers

Screenshots are captured during session replay in the following cases:

- User taps anywhere on the screen.
- User navigates between activities or fragments.
- Screen layout changes.
- Error or crash occurs.
- Manual screen capture event via [`SessionReplay.captureScreenshot()`](#manually-capture-screen).

Android Session Replay combines a 1 FPS layout-change sampling ***\*with* \*event-based captures** (click, error), so you still see key moments even if they occur between checks

## Start and stop recording

If `autoStartSessionRecording` is `false`, you can manually control recording:

```kotlin
SessionReplay.startSessionRecording()
SessionReplay.stopSessionRecording()
```

## Manually capture screen

Use `captureScreenshot` to capture a specific moment in the session:

```kotlin
SessionReplay.captureScreenshot()
```

## Shut down Session Replay

Stop the recorder and release its resources. After shutdown, calling `startSessionRecording()` again has no effect until you re-initialize.

```kotlin
SessionReplay.shutdown()
```

## Privacy and masking

Coralogix provides flexible masking options to help you meet privacy requirements:

- **Text masking**: Use `maskAllTexts` to redact all on-screen text, or selectively mask only input fields via `maskInputFieldsOfTypes`.
- **Input field masking**: Protect sensitive data such as passwords, emails, phone numbers, and credit card fields by specifying their `EditTextType`.
- **View masking**: You can programmatically mark a specific view as sensitive:

```kotlin
mySensitiveView.maskView()
```

This ensures that the view’s contents are blurred in session replays.

> **Tip:** Always verify your masking rules in staging before going live, especially for sensitive inputs like login screens and payment forms.