Drones, like any other aircraft, are limited in range and thus need to land to refuel or recharge, but this could change.
Boeing received a patent this week for an autonomous drone which can recharge while it's in the air, meaning it could theoretically fly forever without needing to land. The drone would have a retractable tether cable, which would connect to a power source on the ground, automatically disconnecting when it is fully charged.
The power source could also be installed in the ocean, or attached to a moving vehicle, giving this tech great flexibility.
Boeing hasn't given any indication as to whether or not they will develop this any further, but it seems too exciting and useful not to. It would be especially useful for drone delivery services, if they ever take off.
The main issue I foresee is charging times could be long (depending on the battery capacity of the drone), so it might not be practical until battery tech evolves to the point where faster charging is possible.
For a more in depth look into this, check out this video from PatentYogi below.