The 27-year-old actor and Emily, 24, were also joined by the director of the film, Max Joseph. You may recognize Max from his MTV reality show Catfish!
Earlier in the day, all three were seen leaving the BBC Radio 1 studios and greeting fans.
Emily and Zac were seen whipping out a selfie stick to commemorate the day!
We Are Your Friends is set to be released on August 27 in the UK and a day later in the US.
FYI: Emily is wearing a Zimmerman dress, Brian Atwood boots, Ileana Makri earrings and cufflinks, and a ring by Graziela Gems.
15+ pics inside of Zac Efron…