OPush is an implement of the Exchange ActiveSync protocol supporting versions 2.5 and 12.1 of the protocol (Exchange 2003 and 2007). It is implemented with Eclipse and OSGi technologies and allows customized data providers. A default data provider implementation is available for the OBM groupware solution.
HordeZpush provides ActiveSync synchronisation between smartphones, PDAs, and Horde groupware. It is based on the Zpush project and adds backends that synchronize contacts and calendars with Horde. It has been tested with Horde 3.3.5, Kronolith 2.3.2, Turba 2.3.2, and Z-Push 1.2.1.