Drone software is largely based on the Flight Control Unit chosen. There are both open source and commercial software packages available -so required capabilities and personal preference become the largest factors in the decision.
The leading autonomous software so far appears to be an open source open hardware project called APM. Their flight control units can be used on planes, rovers, and a variety of multi rotor configurations. Because it is open source, numerous developers have come up with essential improvements and compatible control software. APM drives many of the commercial drones on the market today.