"Apt." is a song by New Zealand and South Korean singer Rosé and American singer-songwriter Bruno Mars. It was released through The Black Label and Atlantic Records on 18 October 2024, as the lead single from the former's upcoming debut studio album, Rosie (2024). It marks Rosé's first solo single in three years and her first release since departing from YG Entertainment and Interscope Records as a solo artist in 2023.