Use the following commands to list or search for specific ActiveSync devices.
$Mailboxes = Get-Mailbox -Database <DBName> | Select Identity
or
$Mailboxes = Get-CasMailbox -ResultSize Unlimited | Select Identity
Then
$Devices = ForEach ($Mailbox in $Mailboxes) {Get-ActiveSyncDevice -Mailbox $Mailbox.Identity | Where {$_.DeviceOS -like "iOS 6.1*"}} $Devices | Format-List UserDisplayName, DeviceID, DeviceType, DeviceModel, DeviceOS, DeviceAccessState
Change the “where” command to search for other parameters such as DeviceType or DeviceModel.