Here is a good SyncML overview with nice pictures that covers some of the software ScheduleWorld can sync with.

Basically any software or device that conforms to the SyncML open standard will work. The following clients are known to work well.

• The Community Projects page provides links to SyncML clients/plug-ins for Exchange, Domino, SugarCRM, Mozilla, LDAP, BlackBerry, Palm, and others.

• Commercial (free trial) SyncML clients.
• Note: currently you need to enable a specific date format for birthdays to work. You can read more about it in the forums.

• A new synchronization extension for Thunderbird address books. If you install the optional Lightning extension SyncSW will sync the calendar event and todo data as well.
• Lightning 0.3.1 or greater will work.
• Sunbird 0.5 will work.
• Thunderbird 1.5 or greater will work.

• A well tested SyncML client for Evolution.
  NOTE: See the preferences page (login required) for SyncEvolution configuration information.
  NOTE: here is a good article for Ubuntu users

• Keeps your Apple iCal calendars in sync with Google Calendar.

• Local Time: Some phones ignore timezone information and/or UTC formatted data. This means ScheduleWorld has to manually convert dates and times to/from your configured timezone into a local time format.
  Since some phones work properly and some phones do not - and since manufacturers do not document they have problems handling timezone data or UTC dates you have to sync with and without 'Local Time' enabled to figure out how your phone works.
• Fix DST: some phones seem to get DST times wrong. Enabling this option tells ScheduleWorld to account for this.
• Import Photo: some phones can export contact photos but not import contact jpeg photos. If you enable this ScheduleWorld will include contact jpeg photos while syncing to the phone.

Some cell phones fail to sync and report 'sync incomplete'. This usually happens when the phone sync program does not select the correct access point.

It has been reported that with Nokia 6620 devices (other series 60 and Symbian-based phones may be similar) if you use your phone's web browser to connect to http://sync.scheduleworld.com/funambol/ds , then start the sync (leaving the web browser running by pressing the red button and then returning to the menu). The sync should work perfectly.

Blackberry devices normally sync fine. However, there seems to be one problem with at least one particular firmware revision: the device loses its APN settings in the "TCP Settings" section when you turn off the device.

• 7230 Blackberry.
• On the Vodafone network.
• BWC (Blackberry Web Client).
• Firmware/OS version:4.0.0.171.
• BWC is different than the BES (Enterprise Service) as BWC doesn't have full data services (MDS) enabled.
• Full data/TCP access is enabled through a seperate GPRS APN which had to get provisioned manually.

Also, the Blackberry does not seem to work if you provide the SyncML software the APN + gateway + port. If you omit the gateway from the client configuration it seems to default to the "TCP Settings" and it works.

Recently I found a forum that might contain some useful information:
http://www.blackberryforums.com/archive/index.php/t-2185.html

New versions of the Sync4j BB client have the calendar sync disabled. Apparently this is because of a device bug. However, one user has reported that after having trouble syncing with the currently supported version (1.1.5) upgrading to 1.2.3 and then downgrading to 1.1.5 fixed the problem. Hopefully this helps someone with their BlackBerry.

A ScheduleWorld user tried to sync his Treo 650 CDMA phone with his ScheduleWorld account using the Synthesis SyncML client. The Synthesis software (palm client V2.1.0.42) worked, but he initially kept getting a "database not found" error.

The "database not found" error was caused because the palm client was sending "cal?/dr(-30,90)" instead of just "cal". The solution was to uncheck the date range option (30 days before and 90 days after the current date).