Powershell: Sorting and display the most recent duplicate in a custom object (by username)

Question

I'm looking for some suggestions/tips on how to sort and display the most recent record in a custom object (by a username). Basically, I am in a situation where I have an ActiveSync report with multiple usernames showing up on the report but I only want the most recent user's device information like device version , last contact time, etc... (See below the custom object's fields)

I've tried the following code but I am not getting the results I am looking for.

  $ActiveSyncImport | Group-Object Identity| foreach-object { $_.group | sort-object LastSuccessSync | select -last 1}

Any help would be greatly appreciated

**Update as of 9/10/2013 at 8:40pm MST:

The output I am trying to get is like the following:

    DeviceOS                               DeviceID                                                                            
    --------                               --------                                                                            
                                           ApplDMPFWGAADFHW                                                                    
    Windows Phone7.10.7720                 C3F755AAEB6CDE163838A106B00382F8                                                    
    Android 4.2.2                          3939303030303238323236343838  

But, when I use my one-line of code I get the same results as my original ActiveSync Information not sorted or grouped.

ActiveSync Information:

    RunspaceId                    : be1d8592-a70a-4322-a146-f6569a067af6
    SamAccountName                : 
    FirstSyncTime                 : 4/8/2013 9:49:31 PM
    LastPolicyUpdateTime          : 4/8/2013 9:50:41 PM
    LastSyncAttemptTime           : 9/9/2013 4:06:13 AM
    LastSuccessSync               : 9/9/2013 4:06:13 AM
    DeviceType                    : iPhone
    DeviceID                      : ApplC39xxxP9DDP7
    DeviceUserAgent               : Apple-iPhone3C3/1002.329
    DeviceWipeSentTime            : 
    DeviceWipeRequestTime         : 
    DeviceWipeAckTime             : 
    LastPingHeartbeat             : 900
    RecoveryPassword              : ********
    DeviceModel                   : iPhone3C3
    DeviceImei                    : 
    DeviceFriendlyName            : Black iPhone 4
    DeviceOS                      : iOS 6.1.3 10B329
    DeviceOSLanguage              : en
    DevicePhoneNumber             : 
    MailboxLogReport              : 
    DeviceEnableOutboundSMS       : False
    DeviceMobileOperator          : 
    Identity                      : corp.XXXX.com/NorthAmerica/Users/lastname, firstname/ExchangeActiveSyncDevices/iPhone§ApplC39xxxP9DDP7
    Guid                          : e7712106-3643-XXXX-XXXX-e20fa4376ad9
    IsRemoteWipeSupported         : True
    Status                        : DeviceOk
    StatusNote                    : 
    DeviceAccessState             : Allowed
    DeviceAccessStateReason       : Global
    DeviceAccessControlRule       : 
    DevicePolicyApplied           : Default ActiveSync Policy
    DevicePolicyApplicationStatus : AppliedInFull
    LastDeviceWipeRequestor       : 
    DeviceActiveSyncVersion       : 14.1
    NumberOfFoldersSynced         : 12
    SyncStateUpgradeTime          :