app (n.) 1. originally from computer software app*lication; 2 (n.) bio smartphone and tablet app*endages, most commonly specimens of Homo sapiens.
When extraterrestrials finally arrived on Earth circa 2021 for a look around, they discovered that the dominant life forms were evolved digital communications devices. Subsequent investigation suggested that these creatures had only recently emerged on the scene, and at first the aliens couldn’t see what had given rise to them.
But then one team noticed tiny bio appendages dangling from many of the endemic Smartphone and Tablet spp. Even as the digital beings had developed, their evolutionary antecedents had shriveled to largely vestigial organs, more decorative than functional. Later investigations revealed that a pre-Homo app specimen of Homo sapiens, one designated Collin Piprell according to prevailing naming conventions, had foreseen these developments in something he referred to as a central irony of their age. 
Other Earthly species had already undergone parallel developments. One such example was Haplophryne mollis. “When scientists first started capturing ceratioid anglerfish, they noticed that all of the specimens were female. These individuals were a few centimetres in size and almost all of them had what appeared to be parasites attached to them. It turned out that these “parasites” were highly reduced male ceratioids.”
Female anglerfish with atrophied males attached.