The GDL-60 is a Datalink unit that enables Garmin's PlaneSync technology.  PlaneSync is a aircraft connectivity feature that automatically updates avionics databases, and, depending on the installation, can log flight/engine data and remotely check fuel & systems status from the Garmin Pilot application.  The GDL-60 also provides use Connext to stream weather, traffic, AHRS, flight plans, and other data from avionics to flight apps such as Garmin Pilot and ForeFlight.