Application Inventory Report

<#
.TITLE
    Application Inventory Report

.SYNOPSIS
    Generate a comprehensive application inventory report for all managed devices in Intune.

.DESCRIPTION
    This script connects to Microsoft Graph, retrieves all managed devices and their installed applications,
    and generates detailed reports in both CSV and HTML formats. The report includes application details,
    installation status, version information, and summary statistics across the entire device fleet.

.TAGS
    Apps,Reporting

.MINROLE
    Intune Administrator

.PERMISSIONS
    DeviceManagementManagedDevices.Read.All,DeviceManagementApps.Read.All

.AUTHOR
    Ugur Koc

.VERSION
    1.0

.CHANGELOG
    1.0 - Initial release

.LASTUPDATE
    2025-05-29

.EXAMPLE
    .\get-application-inventory-report.ps1
    Generates application inventory reports for all managed devices

.EXAMPLE
    .\get-application-inventory-report.ps1 -OutputPath "C:\Reports" -IncludeSystemApps
    Generates reports including system applications and saves them to the specified directory

.EXAMPLE
    .\get-application-inventory-report.ps1 -FilterByPublisher "Microsoft Corporation" -OpenReport
    Generates reports filtered by Microsoft applications and opens the HTML report

.EXAMPLE
    .\get-application-inventory-report.ps1 -ForceModuleInstall
    Forces module installation without prompting and generates the report

.NOTES
    - Requires Microsoft.Graph.Authentication module: Install-Module Microsoft.Graph.Authentication
    - Requires appropriate permissions in Azure AD
    - Large tenants may take considerable time to complete due to API rate limits
    - Reports are saved in both CSV and HTML formats
    - System applications are excluded by default to focus on business applications
    - Uses beta endpoint for enhanced application data
    - Disclaimer: This script is provided AS IS without warranty of any kind. Use it at your own risk.
#>

[CmdletBinding()]
param(
    [Parameter(Mandatory = $false)]
    [string]$OutputPath = ".",
    
    [Parameter(Mandatory = $false)]
    [switch]$IncludeSystemApps,
    
    [Parameter(Mandatory = $false)]
    [string]$FilterByPublisher = "",
    
    [Parameter(Mandatory = $false)]
    [string]$FilterByAppName = "",
    
    [Parameter(Mandatory = $false)]
    [switch]$OpenReport,
    
    [Parameter(Mandatory = $false)]
    [int]$MaxDevices = 0,
    
    [Parameter(Mandatory = $false, HelpMessage = "Force module installation without prompting")]
    [switch]$ForceModuleInstall
)

# ============================================================================
# ENVIRONMENT DETECTION AND SETUP
# ============================================================================

function Initialize-RequiredModule {
    <#
    .SYNOPSIS
    Ensures required modules are available and loaded
    #>
    param(
        [string[]]$ModuleNames,
        [bool]$IsAutomationEnvironment,
        [bool]$ForceInstall = $false
    )
    
    foreach ($ModuleName in $ModuleNames) {
        Write-Verbose "Checking module: $ModuleName"
        
        # Check if module is available
        $module = Get-Module -ListAvailable -Name $ModuleName | Select-Object -First 1
        
        if (-not $module) {
            if ($IsAutomationEnvironment) {
                $errorMessage = @"
Module '$ModuleName' is not available in this Azure Automation Account.

To resolve this issue:
1. Go to Azure Portal
2. Navigate to your Automation Account
3. Go to 'Modules' > 'Browse Gallery'
4. Search for '$ModuleName'
5. Click 'Import' and wait for installation to complete

Alternative: Use PowerShell to import the module:
Import-Module Az.Automation
Import-AzAutomationModule -AutomationAccountName "YourAccount" -ResourceGroupName "YourRG" -Name "$ModuleName"
"@
                throw $errorMessage
            }
            else {
                # Local environment - attempt to install
                Write-Information "Module '$ModuleName' not found. Attempting to install..." -InformationAction Continue
                
                if (-not $ForceInstall) {
                    $response = Read-Host "Install module '$ModuleName'? (Y/N)"
                    if ($response -notmatch '^[Yy]') {
                        throw "Module '$ModuleName' is required but installation was declined."
                    }
                }
                
                try {
                    # Check if running as administrator for AllUsers scope
                    $isAdmin = ([Security.Principal.WindowsPrincipal] [Security.Principal.WindowsIdentity]::GetCurrent()).IsInRole([Security.Principal.WindowsBuiltInRole] "Administrator")
                    $scope = if ($isAdmin) { "AllUsers" } else { "CurrentUser" }
                    
                    Write-Information "Installing '$ModuleName' in scope '$scope'..." -InformationAction Continue
                    Install-Module -Name $ModuleName -Scope $scope -Force -AllowClobber -Repository PSGallery
                    Write-Information "✓ Successfully installed '$ModuleName'" -InformationAction Continue
                }
                catch {
                    throw "Failed to install module '$ModuleName': $($_.Exception.Message)"
                }
            }
        }
        
        # Import the module
        try {
            Write-Verbose "Importing module: $ModuleName"
            Import-Module -Name $ModuleName -Force -ErrorAction Stop
            Write-Verbose "✓ Successfully imported '$ModuleName'"
        }
        catch {
            throw "Failed to import module '$ModuleName': $($_.Exception.Message)"
        }
    }
}

# Detect execution environment
if ($PSPrivateMetadata.JobId.Guid) {
    Write-Output "Running inside Azure Automation Runbook"
    $IsAzureAutomation = $true
}
else {
    Write-Information "Running locally in IDE or terminal" -InformationAction Continue
    $IsAzureAutomation = $false
}

# Initialize required modules
$RequiredModules = @(
    "Microsoft.Graph.Authentication"
)

try {
    Initialize-RequiredModule -ModuleNames $RequiredModules -IsAutomationEnvironment $IsAzureAutomation -ForceInstall $ForceModuleInstall
    Write-Verbose "✓ All required modules are available"
}
catch {
    Write-Error "Module initialization failed: $_"
    exit 1
}

# ============================================================================
# AUTHENTICATION
# ============================================================================

try {
    if ($IsAzureAutomation) {
        # Azure Automation - Use Managed Identity
        Write-Output "Connecting to Microsoft Graph using Managed Identity..."
        Connect-MgGraph -Identity -NoWelcome -ErrorAction Stop
        Write-Output "✓ Successfully connected to Microsoft Graph using Managed Identity"
    }
    else {
        # Local execution - Use interactive authentication
        Write-Information "Connecting to Microsoft Graph with interactive authentication..." -InformationAction Continue
        $Scopes = @(
            "DeviceManagementManagedDevices.Read.All",
            "DeviceManagementApps.Read.All"
        )
        Connect-MgGraph -Scopes $Scopes -NoWelcome -ErrorAction Stop
        Write-Information "✓ Successfully connected to Microsoft Graph" -InformationAction Continue
    }
}
catch {
    Write-Error "Failed to connect to Microsoft Graph: $($_.Exception.Message)"
    exit 1
}

# ============================================================================
# HELPER FUNCTIONS
# ============================================================================

# Function to get all pages of results with rate limiting
function Get-MgGraphAllPage {
    param(
        [string]$Uri,
        [int]$DelayMs = 100
    )
    
    $allResults = @()
    $nextLink = $Uri
    $requestCount = 0
    
    do {
        try {
            # Add delay to respect rate limits
            if ($requestCount -gt 0) {
                Start-Sleep -Milliseconds $DelayMs
            }
            
            $response = Invoke-MgGraphRequest -Uri $nextLink -Method GET
            $requestCount++
            
            if ($response.value) {
                $allResults += $response.value
            }
            else {
                $allResults += $response
            }
            
            $nextLink = $response.'@odata.nextLink'
            
            # Show progress for large datasets
            if ($requestCount % 10 -eq 0) {
                Write-Information "." -InformationAction Continue
            }
        }
        catch {
            if ($_.Exception.Message -like "*429*" -or $_.Exception.Message -like "*throttled*") {
                Write-Information "`nRate limit hit, waiting 60 seconds..." -InformationAction Continue
                Start-Sleep -Seconds 60
                continue
            }
            Write-Warning "Error fetching data from $nextLink : $($_.Exception.Message)"
            break
        }
    } while ($nextLink)
    
    return $allResults
}

# System applications to exclude by default
$SystemApps = @(
    "Microsoft.Windows.*",
    "Microsoft.VCLibs.*",
    "Microsoft.NET.*",
    "Microsoft.UI.*",
    "Microsoft.Services.*",
    "Microsoft.Advertising.*",
    "Microsoft.MicrosoftEdge.*",
    "Windows.*",
    "InputApp",
    "Microsoft.AAD.*",
    "Microsoft.AccountsControl",
    "Microsoft.AsyncTextService",
    "Microsoft.BioEnrollment",
    "Microsoft.CredDialogHost",
    "Microsoft.ECApp",
    "Microsoft.LockApp",
    "Microsoft.MicrosoftEdgeDevToolsClient",
    "Microsoft.Win32WebViewHost",
    "Microsoft.Windows.Apprep.ChxApp",
    "Microsoft.Windows.AssignedAccessLockApp",
    "Microsoft.Windows.CapturePicker",
    "Microsoft.Windows.CloudExperienceHost",
    "Microsoft.Windows.ContentDeliveryManager",
    "Microsoft.Windows.Cortana",
    "Microsoft.Windows.NarratorQuickStart",
    "Microsoft.Windows.ParentalControls",
    "Microsoft.Windows.PeopleExperienceHost",
    "Microsoft.Windows.PinningConfirmationDialog",
    "Microsoft.Windows.SecHealthUI",
    "Microsoft.Windows.SecureAssessmentBrowser",
    "Microsoft.Windows.ShellExperienceHost",
    "Microsoft.Windows.XGpuEjectDialog",
    "Microsoft.XboxGameCallableUI"
)

# ============================================================================
# MAIN SCRIPT LOGIC
# ============================================================================

try {
    Write-Information "Starting application inventory report generation..." -InformationAction Continue

    # Get all managed devices
    Write-Information "Retrieving managed devices..." -InformationAction Continue
    $devicesUri = "https://graph.microsoft.com/v1.0/deviceManagement/managedDevices"
    if ($MaxDevices -gt 0) {
        $devicesUri += "?`$top=$MaxDevices"
    }
    $devices = Get-MgGraphAllPage -Uri $devicesUri
    Write-Information "`n✓ Found $($devices.Count) managed devices" -InformationAction Continue

    # Create application inventory array
    $applicationInventory = @()
    $processedDevices = 0
    $totalApplications = 0

    Write-Information "Processing device applications..." -InformationAction Continue

    foreach ($device in $devices) {
        $processedDevices++
        Write-Progress -Activity "Processing Device Applications" -Status "Processing device $processedDevices of $($devices.Count): $($device.deviceName)" -PercentComplete (($processedDevices / $devices.Count) * 100)
    
        try {
            # Use the beta endpoint with expand to get detected apps for each device
            $deviceAppsUri = "https://graph.microsoft.com/beta/deviceManagement/managedDevices/$($device.id)?`$expand=detectedApps"
            Write-Verbose "Processing device: $($device.deviceName) (ID: $($device.id))" -Verbose
            Write-Verbose "API URL: $deviceAppsUri" -Verbose
            $deviceWithApps = Invoke-MgGraphRequest -Uri $deviceAppsUri -Method GET
        
            if ($deviceWithApps.detectedApps) {
                foreach ($app in $deviceWithApps.detectedApps) {
                    # Skip system apps if not included
                    if (-not $IncludeSystemApps) {
                        $isSystemApp = $false
                        foreach ($systemApp in $SystemApps) {
                            if ($app.displayName -like $systemApp) {
                                $isSystemApp = $true
                                break
                            }
                        }
                        if ($isSystemApp) { continue }
                    }
                
                    # Apply filters if specified
                    if ($FilterByPublisher -and $app.publisher -notlike "*$FilterByPublisher*") {
                        continue
                    }
                
                    if ($FilterByAppName -and $app.displayName -notlike "*$FilterByAppName*") {
                        continue
                    }
                
                    # Calculate days since last seen
                    $daysSinceLastSeen = if ($device.lastSyncDateTime) {
                        [math]::Round(((Get-Date) - [DateTime]$device.lastSyncDateTime).TotalDays, 1)
                    }
                    else {
                        "Never"
                    }
                
                    # Create application inventory entry
                    $appEntry = [PSCustomObject]@{
                        DeviceName          = $device.deviceName
                        DeviceId            = $device.id
                        UserPrincipalName   = $device.userPrincipalName
                        UserDisplayName     = $device.userDisplayName
                        OperatingSystem     = $device.operatingSystem
                        OSVersion           = $device.osVersion
                        ApplicationName     = $app.displayName
                        ApplicationVersion  = $app.version
                        Publisher           = if ($app.publisher) { $app.publisher } else { "Unknown" }
                        ApplicationSize     = if ($app.sizeInByte -and $app.sizeInByte -gt 0) { [math]::Round($app.sizeInByte / 1MB, 2) } else { "Unknown" }
                        ApplicationSizeUnit = if ($app.sizeInByte -and $app.sizeInByte -gt 0) { "MB" } else { "N/A" }
                        Platform            = if ($app.platform) { $app.platform } else { "Unknown" }
                        LastSyncDateTime    = $device.lastSyncDateTime
                        DaysSinceLastSync   = $daysSinceLastSeen
                        DeviceModel         = $device.model
                        DeviceManufacturer  = $device.manufacturer
                        EnrollmentType      = $device.managementState
                        OwnerType           = $device.managedDeviceOwnerType
                        ComplianceState     = $device.complianceState
                        ApplicationId       = $app.id
                    }
                
                    $applicationInventory += $appEntry
                    $totalApplications++
                }
            }
        
            # Add a small delay to respect rate limits
            Start-Sleep -Milliseconds 100
        }
        catch {
            if ($_.Exception.Message -like "*429*" -or $_.Exception.Message -like "*throttled*") {
                Write-Information "`nRate limit hit, waiting 60 seconds..." -InformationAction Continue
                Start-Sleep -Seconds 60
                # Retry the same device
                $processedDevices--
                continue
            }
            Write-Warning "Error processing applications for device $($device.deviceName): $($_.Exception.Message)"
        }
    }

    Write-Progress -Activity "Processing Device Applications" -Completed

    # Generate summary statistics
    $uniqueApplications = $applicationInventory | Group-Object ApplicationName | Measure-Object | Select-Object -ExpandProperty Count
    $uniquePublishers = $applicationInventory | Group-Object Publisher | Measure-Object | Select-Object -ExpandProperty Count
    $uniqueDevices = $applicationInventory | Group-Object DeviceName | Measure-Object | Select-Object -ExpandProperty Count

    # Get top applications by device count
    $topApplications = $applicationInventory | Group-Object ApplicationName | 
    ForEach-Object { 
        [PSCustomObject]@{
            ApplicationName = $_.Name
            DeviceCount     = $_.Count
            UniqueVersions  = ($_.Group | Group-Object ApplicationVersion | Measure-Object).Count
            Publishers      = ($_.Group | Group-Object Publisher | Select-Object -First 1).Name
        }
    } | Sort-Object DeviceCount -Descending | Select-Object -First 10

    # Get top publishers by application count
    $topPublishers = $applicationInventory | Group-Object Publisher | 
    ForEach-Object { 
        [PSCustomObject]@{
            Publisher        = $_.Name
            ApplicationCount = ($_.Group | Group-Object ApplicationName | Measure-Object).Count
            DeviceCount      = $_.Count
        }
    } | Sort-Object ApplicationCount -Descending | Select-Object -First 10

    # Generate timestamp for file names
    $timestamp = Get-Date -Format "yyyy-MM-dd_HH-mm-ss"
    $csvPath = Join-Path $OutputPath "Intune_Application_Inventory_Report_$timestamp.csv"
    $htmlPath = Join-Path $OutputPath "Intune_Application_Inventory_Report_$timestamp.html"

    # Export to CSV
    try {
        $applicationInventory | Export-Csv -Path $csvPath -NoTypeInformation -Encoding UTF8
        Write-Information "✓ CSV report saved: $csvPath" -InformationAction Continue
    }
    catch {
        Write-Error "Failed to save CSV report: $($_.Exception.Message)"
    }

    # Generate HTML report
    try {
        $htmlContent = @"
<!DOCTYPE html>
<html>
<head>
    <title>Intune Application Inventory Report</title>
    <style>
        body { font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif; margin: 20px; background-color: #f5f5f5; }
        .header { background-color: #0078d4; color: white; padding: 20px; border-radius: 8px; margin-bottom: 20px; }
        .summary { background-color: white; padding: 15px; border-radius: 8px; margin-bottom: 20px; box-shadow: 0 2px 4px rgba(0,0,0,0.1); }
        .summary-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: 15px; margin-bottom: 20px; }
        .summary-item { text-align: center; padding: 10px; background-color: #f8f9fa; border-radius: 4px; }
        .summary-number { font-size: 24px; font-weight: bold; color: #0078d4; }
        .top-lists { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; margin-bottom: 20px; }
        .top-list { background-color: white; padding: 15px; border-radius: 8px; box-shadow: 0 2px 4px rgba(0,0,0,0.1); }
        .top-list h3 { margin-top: 0; color: #0078d4; }
        .top-item { display: flex; justify-content: space-between; padding: 8px 0; border-bottom: 1px solid #e1e5e9; }
        .top-item:last-child { border-bottom: none; }
        table { width: 100%; border-collapse: collapse; background-color: white; border-radius: 8px; overflow: hidden; box-shadow: 0 2px 4px rgba(0,0,0,0.1); }
        th { background-color: #0078d4; color: white; padding: 12px; text-align: left; font-weight: 600; position: sticky; top: 0; }
        td { padding: 10px 12px; border-bottom: 1px solid #e1e5e9; }
        tr:nth-child(even) { background-color: #f8f9fa; }
        tr:hover { background-color: #e3f2fd; }
        .footer { margin-top: 20px; text-align: center; color: #6c757d; font-size: 12px; }
        .filter-info { background-color: #fff3cd; border: 1px solid #ffeaa7; padding: 10px; border-radius: 4px; margin-bottom: 20px; }
    </style>
</head>
<body>
    <div class="header">
        <h1>Intune Application Inventory Report</h1>
        <p>Generated on: $(Get-Date -Format "dddd, MMMM dd, yyyy 'at' HH:mm:ss")</p>
    </div>
"@

        # Add filter information if filters were applied
        if ($FilterByPublisher -or $FilterByAppName -or $IncludeSystemApps -or $MaxDevices -gt 0) {
            $htmlContent += "<div class='filter-info'><strong>Applied Filters:</strong> "
            if ($FilterByPublisher) { $htmlContent += "Publisher: $FilterByPublisher | " }
            if ($FilterByAppName) { $htmlContent += "Application: $FilterByAppName | " }
            if ($IncludeSystemApps) { $htmlContent += "Including System Apps | " }
            if ($MaxDevices -gt 0) { $htmlContent += "Max Devices: $MaxDevices | " }
            $htmlContent = $htmlContent.TrimEnd(" | ") + "</div>"
        }

        $htmlContent += @"
    <div class="summary">
        <h2>Summary</h2>
        <div class="summary-grid">
            <div class="summary-item">
                <div class="summary-number">$totalApplications</div>
                <div>Total Application Instances</div>
            </div>
            <div class="summary-item">
                <div class="summary-number">$uniqueApplications</div>
                <div>Unique Applications</div>
            </div>
            <div class="summary-item">
                <div class="summary-number">$uniquePublishers</div>
                <div>Unique Publishers</div>
            </div>
            <div class="summary-item">
                <div class="summary-number">$uniqueDevices</div>
                <div>Devices with Applications</div>
            </div>
        </div>
        
        <div class="top-lists">
            <div class="top-list">
                <h3>Top 10 Applications by Device Count</h3>
"@

        foreach ($app in $topApplications) {
            $htmlContent += "<div class='top-item'><span>$($app.ApplicationName)</span><span>$($app.DeviceCount) devices</span></div>"
        }

        $htmlContent += @"
            </div>
            <div class="top-list">
                <h3>Top 10 Publishers by Application Count</h3>
"@

        foreach ($publisher in $topPublishers) {
            $htmlContent += "<div class='top-item'><span>$($publisher.Publisher)</span><span>$($publisher.ApplicationCount) apps</span></div>"
        }

        $htmlContent += @"
            </div>
        </div>
    </div>
    
    <div class="summary">
        <h2>Detailed Application Inventory</h2>
        <table>
            <thead>
                <tr>
                    <th>Device Name</th>
                    <th>User</th>
                    <th>Application Name</th>
                    <th>Version</th>
                    <th>Publisher</th>
                    <th>Platform</th>
                    <th>Size (MB)</th>
                    <th>OS</th>
                    <th>Last Sync</th>
                </tr>
            </thead>
            <tbody>
"@

        foreach ($app in $applicationInventory | Sort-Object DeviceName, ApplicationName) {
            $sizeDisplay = if ($app.ApplicationSize -ne "Unknown") { "$($app.ApplicationSize) $($app.ApplicationSizeUnit)" } else { "Unknown" }
            $htmlContent += @"
                <tr>
                    <td>$($app.DeviceName)</td>
                    <td>$($app.UserDisplayName)</td>
                    <td>$($app.ApplicationName)</td>
                    <td>$($app.ApplicationVersion)</td>
                    <td>$($app.Publisher)</td>
                    <td>$($app.Platform)</td>
                    <td>$sizeDisplay</td>
                    <td>$($app.OperatingSystem) $($app.OSVersion)</td>
                    <td>$($app.LastSyncDateTime)</td>
                </tr>
"@
        }

        $htmlContent += @"
            </tbody>
        </table>
    </div>
    
    <div class='footer'>Report generated by Intune Application Inventory Script v1.0</div>
</body>
</html>
"@

        $htmlContent | Out-File -FilePath $htmlPath -Encoding UTF8
        Write-Information "✓ HTML report saved: $htmlPath" -InformationAction Continue
    
        if ($OpenReport) {
            Start-Process $htmlPath
        }
    }
    catch {
        Write-Error "Failed to generate HTML report: $($_.Exception.Message)"
    }

    # Display summary
    Write-Output ""
    Write-Information "📱 APPLICATION INVENTORY SUMMARY" -InformationAction Continue
    Write-Information "=================================" -InformationAction Continue
    Write-Information "Total Application Instances: $totalApplications" -InformationAction Continue
    Write-Information "Unique Applications: $uniqueApplications" -InformationAction Continue
    Write-Information "Unique Publishers: $uniquePublishers" -InformationAction Continue
    Write-Information "Devices Processed: $uniqueDevices" -InformationAction Continue

    if ($topApplications.Count -gt 0) {
        Write-Information "`nTop 5 Most Common Applications:" -InformationAction Continue
        $topApplications | Select-Object -First 5 | ForEach-Object {
            Write-Information "  • $($_.ApplicationName): $($_.DeviceCount) devices" -InformationAction Continue
        }
    }

    Write-Information "`nReports saved to:" -InformationAction Continue
    Write-Information "📄 CSV: $csvPath" -InformationAction Continue
    Write-Information "🌐 HTML: $htmlPath" -InformationAction Continue

    Write-Information "`n🎉 Application inventory report generation completed successfully!" -InformationAction Continue
}
catch {
    Write-Error "Script execution failed: $($_.Exception.Message)"
    exit 1
}
finally {
    # Disconnect from Microsoft Graph
    try {
        Disconnect-MgGraph | Out-Null
        Write-Information "✓ Disconnected from Microsoft Graph" -InformationAction Continue
    }
    catch {
        # Ignore disconnection errors - this is expected behavior when already disconnected
        Write-Verbose "Graph disconnection completed (may have already been disconnected)"
    }
}