Almost everyone is nervous about sharing the specifics of their calendar. CrossPathz is a privacy first geo-social calendar that allows you to see when your path will cross those of your friends without having to share specific appointments (unless you choose to). CrossPathz presents your day on a map and shows where friends will be nearby in the future.
In this example CrossPathz is set to notify you if a friend will be within a one mile radius of your planned route. There is an entry in your plans agenda view that says next Thursday at 1.46pm, David will be within 1 mile. An icon is displayed on the map. David is not at that location now, the icon is placed roughly where David will be assuming he undertakes his own travel plans. David's precise location is obfuscated for privacy reasons.
For more information see CrossPathz FAQs