Its tail ends with a dexterous, handlike appendage. However, because it uses the tail so much, Aipom's real hands have become rather clumsy.
(From Bulbapedia) Aipom is a monkey-like Pokémon with a three-fingered hand at the end of its tail. Its fur is purple, while the skin of its face, inner ears, belly, feet, and the tip of its tail is beige. On its face are a usually cheeky smile and round, blue eyes. Supplemented by its round ears, Aipom's head is disproportionately large compared to its body. Atop its head is a cowlick that is longer on females than males. Unlike its feet, Aipom's arms are simple, purple stubs.
Aipom uses its powerful tail freely and cleverly for many purposes. The tail is strong enough to anchor Aipom to a branch and suspend the rest of its body in the air, but also delicate enough to pick fruit and manipulate objects. Aipom has been known to wrap its tail around tree branches as it sleeps so it does not fall. Since Aipom uses its tail so much, its actual arms are not as dexterous and become clumsy over time. Aipom lives high in the treetops, using its tail for balance as it swings from branch to branch. In Alola, Bounsweet is its favorite food.
(From Bulbapedia) Aipom appears to be based on a monkey and the exaggerated concept of a prehensile tail. It may be specifically based on the squirrel monkey, which is similar in appearance. Aipom also shares its large smile with a cymbal-banging monkey toy. It is also similar to an ahuizotl, a creature of Aztec mythology with monkey hands and a fifth human hand on its tail.
(From Bulbapedia) Aipom and Eipam may be a combination of ape and palm (referring to the hand on its tail). It may also refer to a pom-pom.