Apple's website says "Use Handoff with favorite apps like Mail, Safari, Pages, Numbers, Keynote, Maps, Messages, Reminders, Calendar, and Contacts. And developers can build Handoff into their apps now, too." For me, handoff is only working with the following pre-installed apps: Maps, messages, calendar, and safari. Anyone else having issues with certain apps? Not working for me with mail, reminders, and contacts. Edit: This is between Yosemite Public Beta (newest release) and iOS 8.1 Beta 2.