Your call history, contacts, whitelisted and blacklisted numbers are stored locally on your computer, not on PhoneTray server. Only you have access to that data.
If you have the "Block calls from telemarketers in PhoneTray online anti-spam database" option enabled on the Privacy - Call Blocking screen, PhoneTray will send incoming numbers to our server to check against the database.
PhoneTray will not send numbers on your contact list, white list or black list to our server. All calls from those numbers are processed locally and never sent to our server. If you have privacy concerns you can disable online database on the Call Blocking screen and PhoneTray will not send anything to our server.
When adding a number to your black list you can report that number as spam to the PhoneTray online database but it's completely optional. You can also report a number as legitimate when adding it to your white list. This is optional as well.