Reply To: Exchange – Trying to get list of all users with mobile devices.

Sounds like you want exactly what is described in example 2 from the Get-ActiveSyncDeviceStatistics help:

EXAMPLE 2

This example uses the Get-CASMailbox cmdlet to determine who in the organization has a Microsoft Exchange ActiveSync mobile device. For each mobile device, the Exchange ActiveSync device statistics are retrieved.

$UserList = Get-CASMailbox -Filter {hasactivesyncdevicepartnership -eq $true -and -not displayname -like “CAS_{*”} | Get-Mailbox

$UserList | foreach { Get-ActiveSyncDeviceStatistics -Mailbox $_}