Skype for Business Online has been updated to provide usage data using PowerShell.

If you want to get usage data, you need to have the Skype for Business Online PowerShell modules installed (https://www.microsoft.com/en-us/download/details.aspx?id=39366)

Then you need to connect to your tenant and use the Get-CsUserSession cmdlet

Connect to your tenant – NOTE if your are in hybrid mode with your On Premises Lync/Skype for Business environment you need to use an online account (@yourtenant.onmicrosoft) or you may get an error

$cred = Get-Credential

$session = New-CsOnlineSession -Credential $cred

Import-PSSession $session

Then run the command to get usage data – this example provides usage data from April 1st 2016

Get-CsUserSession –User <Skype User Logon> -StartTime "04/01/2016 00:00:00 AM"

Sample report which provides the client used, the logon time, activities….

RunspaceId            : 0837d992-ecac-4f5a-a6dc-d22623b2dc16
DialogId              : <PII:H101(pkyUuftLwpYy+0HIHUX39Lc/2EQuvKPNaEicEsGL2OU=)>@<domain>_9FEB17DE-0F16-5267-86
                        1D-B0DCA0659C12_071e321f-00f0-457f-884f-4f70c4df8ca1
ReplacesDialogId      :
StartTime             : 6/25/2016 4:01:46 PM
EndTime               :
FromUri               : <Skype User Logon>
ToUri                 : <Skype User Logon>
FromClientVersion     : UCCAPI/16.0.6965.5266 OC/16.0.6965.2053 (Skype for Business)
ToClientVersion       : RTC/7.0
FromTelNumber         :
ToTelNumber           :
ToEndpointId          :
FromEndpointId        : 9FEB17DE-0F16-5267-861D-B0DCA0659C12
ConferenceUrl         :
ConfInstance          :
OnBehalfOfUri         :
ReferredByUri         :
ResponseCode          :
MediaTypesDescription : [RegisterEvent]
ErrorReports          :
QoEReport             :