- FRANTS, Pdogg, "hitman" bang, Hwang Hyun, Eunha, Hannah Robinson, Richard Phillips, Alex Nese, Chendy, Yuju, Noh Joo-hwan, Kim Jin, Gu Yeo-reum, Lee Seu-ran
- FRANTS, Pdogg, "hitman" bang
There are currently two recorded versions of "Apple" found in GFIREND's discography. These versions are:
- Found on the 回:Song of the Sirens mini-album as track #1.
- Apple -JP ver.-
- Found on the 回:Song of the Sirens ~Apple~ digital single as track #1. This is the standard version with Japanese lyrics.