The ability to synchronize Daylite with the iPhone is available as of Daylite v3.5 and upwards.

If you would like to synchronize your Daylite Contacts and Calendar Appointments with your iPhone using older versions of Daylite, you'll need to use the software's existing capabilities.
* Please note that Tasks are not currently supported.

Daylite Contacts will need to be synchronized with the Address Book.
Daylite Calendar appointments will need to be exported, and imported into iCal. (How can I export the Daylite calendar to iCal?)

You can then synchronize the iPhone to the Address Book and iCal.

For more information on how to synchronize Daylite with the Address Book, and export the Daylite Calendar appointments, please refer to the Daylite 3 manual.