Principal differences are shown as to the number and size of newly formed droplets after the collision of spheres, disks, and ellipsoids as well as critical Weber numbers sufficient for intense atomization. The typical breakup times differ for the sphere - sphere, sphere - disk, and sphere - ellipsoid systems within 5-7%, and the number and total surface areas of post-collision droplets in such systems vary several-fold (sometimes, by more than an order of magnitude). We compare three droplet disruption modes: disintegration of a bridge between variously shaped droplets, inflation of a target droplet (usually a disk or ellipsoid) by a projectile droplet (mostly sphere), and aerosol formation induced by the axisymmetric collision of liquid fragments with similar initial shapes. Conditions are determined for the many-fold and, on the contrary, insignificant increase in the number of droplets in an air flow due to their collisions in the breakup mode. (C) 2019 Published by Elsevier B.V.