This article deals with distributed formation control for a set of quadrotors subject simultaneously to external disturbances and switching communication topologies. The proposed robust controller incorporates position and attitude control laws for each quadrotor. Both control laws have a nominal part for trajectory tracking and a robust part that compensates for the dynamic model uncertainties and time-varying external disturbances. The devised controller guarantees that the thrust force is bounded with respect to the position error by utilizing saturation functions. The directed communication topology among the quadrotors is considered to be switchable. The formation control performance is guaranteed under switching topologies, and it is demonstrated that all error terms, in closed-loop, converge to a ball centered at the origin with an arbitrarily small radius, achieving uniformly ultimate boundedness. Finally, the performance of the proposed strategy is validated through numerous simulation and experimental examples.