Install a Microsoft Teams application for all users in a tenant

Install-TeamsAppForAllUsers.ps1

[CmdletBinding()]
param (
    [Parameter()]
    [string]
    $appName
)

$users = o365 aad user list --properties "id,displayName" -o json | ConvertFrom-Json
$app = o365 teams app list -o json | ConvertFrom-Json | Where-Object { $_.displayName -eq $AppName }

if ($null -ne $app) {
    $token = o365 util accesstoken get -r "https://graph.microsoft.com" --new
    $users | ForEach-Object { 
        $userName = $_.displayName
        $options = @{
            Method      = "Post"
            Uri         = "https://graph.microsoft.com/beta/users/$($_.id)/teamwork/installedApps"
            ContentType = "application/json"
            Body        = @{
                "[email protected]" = "https://graph.microsoft.com/beta/appCatalogs/teamsApps/$($app.id)"
            } | ConvertTo-Json
            Headers     = @{
                "Authorization" = "Bearer $token"
            }
        }
        try {
            Invoke-RestMethod @options
            Write-Host "$appName succesfully installed for $userName" -ForegroundColor Green
        }
        catch {            
            Write-Host "There was an issue installing $appName for $userName"
            Write-Host $_.Exception.Message
        }
    }
}
else {
    Write-Error "$appName not found in tenant"
}