Amazon is planning to deliver packages via drones. Lots of testing needs to happen before that becomes a viable option. The company has recently begun private trials in Cambridge area of England. When a customer orders something, it is received at a Prime Air fulfillment center, from which a drone is deployed to deliver it.
These Amazon drones use GPS to find their way to the destination and deliver packages reliably. They were used to deliver gadgets and pet food. This service is only available to few customers right now, but that is going to change in the future.
[Source]