The event will be staged at Victoria Park on August 31, having been pushed back to accommodate the 2012 Olympics.
X Factor contestant Misha B, Maverick Sabre and Lianne La Havas will also perform at the event.
There will also be gigs from Skepta, Hadouken!, Zulu Winter and a DJ set from Foals among others.
Ticket holders must be under the age of 18 to attend, but over the age of 13.
Devlin recently unveiled his new music video for 'Watchtower', featuring Ed Sheeran and Jaime Winstone.
He will release his second studio album A Moving Picture in October.
The full lineup is as follows:
Dry The River
Foals (DJ Set)
Lianne La Havas
Pulled Apart By Horses