“APT.” is a 2024 single by ROSÉ and Bruno Mars, released ahead of ROSÉ’s debut studio album, Rosie. The song draws its title and central chant from the Korean drinking game known as Apartment, pronounced “apateu” in Korean. Its energetic pop-rock production and easy group chant helped it spread widely through short-form dance videos, covers, reactions, and social posts. The opening remains useful because listeners can identify the track quickly, even when creators use only a few seconds before a transition or reveal.