I have created a script that goes through every tab in every channel in each team and counts how many there are of each type of tab. Of course, I have excluded the conversation and files tab as it’s in every channel. I created this so there’s an easy and fast way to get statistics on what apps/tabs that are in use.  This probably could be something to show in an executive report. The script utilizes Graph API to get the information it needs.  Some tabs you find by text search and others by app id.

### Team tabs/apps counter                      ###
### Version 1.0                                 ###
### Author: Alexander Holmeset                  ###
### Twitter: twitter.com/alexholmeset           ###
### Blog: alexholmeset.blog                     ###

#Description:

#You specify a Group/team object ID, then the script archives all conversations in every channel for this team in a HTML file.

#Have in mind information protection policies like GDPR when working on information like this.

#Parameters
#Create a Azure App with group read and Appcatalog read rights in Graph API
$clientId = "enter app id here"
$redirectUri = "urn:ietf:wg:oauth:2.0:oob"
$resourceURI = "https://graph.microsoft.com"
$authority = "https://login.microsoftonline.com/common"
#Remove commenting on username and password if you want to run this without a prompt.
#$Office365Username='user@domain'
#$Office365Password='VeryStrongPassword'
#pre requisites
try {
$AadModule = Import-Module -Name AzureAD -ErrorAction Stop -PassThru
}
catch {
throw 'Prerequisites not installed (AzureAD PowerShell module not installed)'
}
$adal = Join-Path $AadModule.ModuleBase "Microsoft.IdentityModel.Clients.ActiveDirectory.dll"
$adalforms = Join-Path $AadModule.ModuleBase "Microsoft.IdentityModel.Clients.ActiveDirectory.Platform.dll"
[System.Reflection.Assembly]::LoadFrom($adal) | Out-Null
[System.Reflection.Assembly]::LoadFrom($adalforms) | Out-Null
$authContext = New-Object "Microsoft.IdentityModel.Clients.ActiveDirectory.AuthenticationContext" -ArgumentList $authority

##option without user interaction
if (([string]::IsNullOrEmpty($Office365Username) -eq $false) -and ([string]::IsNullOrEmpty($Office365Password) -eq $false))
{
$SecurePassword = ConvertTo-SecureString -AsPlainText $Office365Password -Force
#Build Azure AD credentials object
$AADCredential = New-Object "Microsoft.IdentityModel.Clients.ActiveDirectory.UserPasswordCredential" -ArgumentList $Office365Username,$SecurePassword
# Get token without login prompts.
$authResult = [Microsoft.IdentityModel.Clients.ActiveDirectory.AuthenticationContextIntegratedAuthExtensions]::AcquireTokenAsync($authContext, $resourceURI, $clientid, $AADCredential);
}
else
{
# Get token by prompting login window.
$platformParameters = New-Object "Microsoft.IdentityModel.Clients.ActiveDirectory.PlatformParameters" -ArgumentList "Always"
$authResult = $authContext.AcquireTokenAsync($resourceURI, $ClientID, $RedirectUri, $platformParameters)
}
$accessToken = $authResult.result.AccessToken

$apiUrl = 'https://graph.microsoft.com/v1.0/Groups/'
$myProfile = Invoke-RestMethod -Headers @{Authorization = "Bearer $accessToken"} -Uri $apiUrl -Method Get
$GroupsList = $myprofile | select-object Value
$Groups = $GroupsList.Value | Select-Object Id

$tabscount = @()

$apiurl4 = 'https://graph.microsoft.com/v1.0/appCatalogs/teamsApps'
$AppnameList = Invoke-RestMethod -Headers @{Authorization = "Bearer $accessToken"} -Uri $apiUrl4 -Method Get
$appnamelist2 = $appnamelist.value

foreach($Group in $Groups){

   $GroupId = $Group.Id

   $apiUrl5 = "https://graph.microsoft.com/beta/Groups/$Groupid/"
   $GroupsData = Invoke-RestMethod -Headers @{Authorization = "Bearer $accessToken"} -Uri $apiUrl5 -Method Get
   $NameType = $GroupsData | Select-Object resourceProvisioningOptions,DisplayName
   If($nametype.resourceProvisioningOptions -eq 'Team'){

   "Group "+$nameType.displayName+" is Teams enabled and beeing prcessed."

   $apiurl2 = 'https://graph.microsoft.com/v1.0/teams/'+"$Groupid"+'/channels'
   $Teams = Invoke-RestMethod -Headers @{Authorization = "Bearer $accessToken"} -Uri $apiUrl2 -Method Get

   foreach($channels in $Teams){

        $channelsID = ($channels.value).id

        foreach($channelID in $channelsID){

            $apiurl3 = 'https://graph.microsoft.com/v1.0/teams/'+"$Groupid"+'/channels/'+$channelID+'/tabs'
            $Tabs = Invoke-RestMethod -Headers @{Authorization = "Bearer $accessToken"} -Uri $apiUrl3 -Method Get
            $appids = $tabs.value

                foreach($appid in $appids){

                    if($appid.webUrl -like '*maps*'){$tabscount+="Maps"}
                    elseif($appid.webUrl -like '*Forms*'){$tabscount+="Forms"}
                    elseif($appid.webUrl -like '*planner*'){$tabscount+="Planner"}
                    elseif($appid.webUrl -like '*vsts*'){$tabscount+="VSTS"}
                    elseif($appid.webUrl -like '*youtube*'){$tabscount+="YouTube"}
                    elseif($appid.webUrl -like '*stream*'){$tabscount+="Stream"}
                    elseif($appid.webUrl -like '*wiki*'){$tabscount+="Wiki"}
                    elseif($appid.webUrl -like '*excel*'){$tabscount+="Excel"}
                    elseif($appid.webUrl -like '*powerpoint*'){$tabscount+="PowerPoint"}
                    elseif($appid.webUrl -like '*word*'){$tabscount+="Word"}
                    elseif($appid.webUrl -like '*onenote*'){$tabscount+="OneNote"}
                    elseif($appid.webUrl -like '*sharepoint*'){$tabscount+="SharePoint"}
                    elseif($appid.webUrl -like '*website*'){$tabscount+="WebSite"}
                    elseif($appid.webUrl -like '*pdf*'){$tabscount+="PDF"}
                    elseif($appid.webUrl -like '*powerbi*'){$tabscount+="PowerBI"}
                    elseif($appid.webUrl -like '*microsoftteamstabs.test*'){$tabscount+="PowerBI"}
                    else{$tabscount+= ($appnamelist2 | Where-Object id -eq $appid).displayname}

 }
 }

   }

 }
    else {
       "Group "+$nameType.displayName+" is not Teams enabled"
   }
 }
$tabscount | Group-Object | select name,count | Sort-Object count -Descending<span data-mce-type="bookmark" id="mce_SELREST_start" data-mce-style="overflow:hidden;line-height:0" style="overflow:hidden;line-height:0;">&#65279;</span>