We present a novel coordination scheme for online multi-robot coverage with a team of resource-constrained aerial vehicles relying on the PH-tree data structure. We propose a hybrid system architecture where coverage tasks are assigned to robots in a centralized manner, and individual robots plan their paths cooperatively in a distributed fashion. In this way, robots can focus only on local path planning tasks, while a ground station ensures coordination among the team. We show the applicability of our method to various objects and quantitatively evaluate the performance of our solution for various robot team sizes.