Outlook mobile is Microsoft's recommended option for a mobile email client. Many still use Exchange ActiveSync (EAS) based clients, like the native iOS app.
How to upgrade an existing Exchange Server 2013 deployment to Service Pack 1.
Microsoft has announced the release of Exchange Server 2013 Service Pack 1, containing several new features, improvements, and bug fixes.
Microsoft has announced the release of Update Rollup 4 for Exchange Server 2010 Service Pack 1 that is now available for download.