iPhone
The iPhone's vertical mobility is entirely dependent upon external forces. When dropped, it achieves a terminal velocity of approximately 25 metres per second before making contact with the ground, typically screen-first, following an obscure law of physics known colloquially as 'sod's law'.
Whilst various accessories exist to launch iPhones into the air for photographic purposes, the device itself possesses no inherent jumping capability. It remains, in the technical parlance, stationary unless acted upon by outside forces. Its relationship with gravity is one of reluctant submission.
Kangaroo
The red kangaroo (Macropus rufus) represents one of evolution's most spectacular achievements in terrestrial locomotion. Capable of covering 9 metres in a single bound and reaching sustained speeds of 56 kilometres per hour, the kangaroo's jumping prowess has no peer in the mammalian world.
This remarkable ability stems from elastic tendons that store and release energy with 93% efficiency, a figure that would make any engineer weep with envy. At higher speeds, hopping actually becomes more energy-efficient than running, an elegant solution to Australian distances that the iPhone, despite sixteen years of innovation, has entirely failed to replicate.