I wouldn’t draw too many conclusion from Apple patenting stuff, as they seem to do far more patents than products.
Apple’s filing for “Customized location notification” describes a useful tweak to an existing iOS feature that allows users to send and receive custom event-based notifications from friends as they move through preset zones. Currently, Apple’s Find My Friends app in iOS 8 allows users to send current location, or request alerts when a friend passes over a geofence boundary, but lacks tools to integrate automatic text generation or multi-point tracking.
As described, a first user requests that a second user share their location and agree to send and receive notification pushes via text, email string or other form of communication. When accepted, the first device sends over custom notification event data to the second device, including a description of the event and the ability to obtain or automatically generate custom notifications.
From there, the second device may create a route to said event, which can be shared if route sharing is activated, and begin to broadcast custom notifications when it leaves or enters a predetermined geofenced zone.