BirdieSync

Synchronize your contacts and events between your iPhone and Mozilla Thunderbird, Lightning and Sunbird on your PC. Keep your information up to date automatically: every modification on any device is automatically transferred to the other device.

Keep your data private: your personal data is not stored in the cloud. It is directly synchronized between your device and your desktop computer through a secure connection and never goes through any third-party server.

BirdieSync supports: contact photos, multiple address books and calendars, contact groups and categories, recurring events and alarms, ICS, calDAV, WCAP, Google Calendar types.

Note: this app requires BirdieSync on your PC (19.95 €). You can download a fully-functional version and try it out free for 21 days (only Windows is supported).