Devlin started working with a collection of Grime MCs called The OT Crew (Members; Dogzilla/Deeperman etc.). Soon he joined up with The Movement, members included friend and fellow east london Grime MC Ghetts and North London's Wretch 32 and Scorcher. In December 2006 The Movement released their first and only release entitled Tempo Specialists. Devlin's music began to reach commercial radio stations. He made appearances on Kiss FM and BBC Radio 1Xtra with DJs Logan Sama, Tim Westwood and Cameo. Devlin released his second solo mixtape The Art of Rolling in 2008. US rap star Kanye West posted a video on his blog of Devlin's appearance on Grime DVD Practice Hours when he was aged 15.
In 2009, Devlin's first video was aired on Channel AKA. "London City" spent 10 weeks at no.1 on the channel's official video chart. Other videos followed including Community Outcast and Giant.
His debut album, Bud, Sweat and Beers was released on Island Records in 2010. The first single from the album was "Brainwashed", which was released on 8 August 2010 in the UK and debuted on the UK Singles Chart at number 31, and number 11 on the UK R&B Chart. The second single, "Runaway", was released on 24 October 2010, where it debuted at number 15, marking Devlin's most successful single to date. The single was succeeded by the release of the debut album, Bud, Sweat and Beers, which was released on 1 November 2010 and debuted at number 21 on the UK Albums Chart. "London City" entered the UK chart at number 181 following strong digital downloads from the album. The third single released from the album was "Let It Go" featuring British-producer Labrinth. The track, which was released on 31 January 2011, charted at number 59 in the UK based on downloads alone. In January 2011, Devlin appeared on Jessie J's UK version of "Price Tag".
Devlin stated on an interview with Tim Westwood on BBC Radio 1Xtra that his second album will be released in October 2012, and it will be called A Moving Picture. He also released the free 5 track EP "The Director's Cut", which featured long-time collaborators Ghetts and Rawz Artilla, as well as London City Part 2, the sequel to his earlier song.
The release of A Moving Picture has been delayed until February 2013 for reasons unknown. This is following the recent release of "Off With Their Heads" ft Wretch 32 and the announcement of the third single "Rewind" ft. Diane Birch.