Kerio Connect 8.5 introduces a few important new features. As usual, the full list is available at the Release Notes page, but I'll go over some things that doesn't fully explain.
First up, on the mobile side of things, the option to allow unsupported devices via EAS has disappeared from the interface. That's not because Kerio isn't supporting your phone any more - it's because all ActiveSync devices using protocol version from 2.5 to 14.1 are now supported, so there's no reason for that checkbox.
Next, direct Exchange ActiveSync is supported for Outlook 2013. This means that you do not need the Kerio Connector. However, there are serious limitations. These come from limitations of EAS, not from Kerio, so it's not likely much will change. Still, users who don't care about those particular features report that using EAS is smooth and fast.
List of known issues in MS Outlook 2013 and EAS
Calendar, Contact and Task folders cannot be created in EAS accounts.
Calendar and Task folders created in Kerio Connect client cannot be renamed/deleted in EAS accounts.
A new contact folder cannot be synchronized to EAS accounts.
Drafts and Notes are not synchronized to/from MS Outlook 2013 via EAS.
Delivery confirmation for a message doesn't work for the message sent from MS Outlook 2013 via EAS.
Request a read receipt doesn't work for messages read in MS Outlook 2013 via EAS.
Contact group created in Kerio Connect Client cannot be synchronized to EAS accounts.
Task's status, percentage is not synchronized from EAS accounts.
Global Address List (address book) does not appear in MS Outlook 2013 via EAS.
Contact privacy is not synchronized with MS Outlook 2013 via EAS.
Appointment/Meeting item cannot be moved to other calendar folder in the EAS account in MS Outlook 2013.
Rules and Signatures created in MS Outlook 2013 are client only, they are not synchronized to Kerio Connect Client and vice versa.
Out of Office feature is not available in EAS accounts in Outlook 2013.
An acceptation of a forwarded meeting request is sent to the forwarder but not to the organizer.
Travel time is not visible in EAS accounts
Again, these are limitations of the MS Outlook 2013 and Exchange ActiveSync (EAS) implementation. Kerio can't fix these.
There's a new ability to add a sender to your whitelist directly from the Web client. It's easy to miss: you click on their address as shown here, which gives you a menu that includes the option to whitelist.
There are new formatting options for email editor - fonts, indentation, etc. and a new calendar agenda view. See the release notes for more changes.
Sophos Live Protection
There's a new option for Sophos Live Protection. At the cost of some network traffic, this causes a one way hash of the message to be checked against a constantly updated Sopos cloud database. It is enabled by default on new installs, but on upgrades you'll need to turn this on if you want it..
CalDAV clients and Kerio Connect Client can define additional "travel time" for each event in a calendar.
Development continues here. Users can now share folders across multiple servers, there is a distributed SpamAssassin and new node monitoring.