"Day by Day" waa hees dib-u-habeyn ah oo uu duubay heesaha Kuuriyada Koonfureed iyo xubin ka tirsan Red Velvet Joy. Asal ahaan waxaa duubay oo sii daayay labada gabdhood ee loo yaqaan As One sanadkii 1999-kii, heesta ayaa dib loo duubay waxaana la sii daayay Maajo 31, 2021 oo ay soo saartay shirkadda SM Entertainment oo ah raad ka yimid albumkeeda, Hello. "JOY to show off her sentimental vocal in her upcoming new album's B-side track 'Day By Day'!". SM Entertainment.