OfficeTime normally respects the date format of your computer whether it is dd/mm/yy or mm/dd/yy or any other format. This can be changed on your computer:

Mac: Go to the Mac preferences and then International, Formats. On some computers and regions, you may be told the region can only be used by Unicode applications. In that case, OfficeTime will not correctly use the regions date. To fix this, simply choose a region that does not give this message and then select the Customize button in the preference and change the date format to suite. OfficeTime will then follow that date format.

Windows: Select Start-> Control Panel-> Clock-> Language & Region-> Change date, time, or number format.

iPhone/iPad: Go to the iOS Settings (not the OfficeTime Settings), General, Language & Regions and change the region.