This UK foursome are true kids of the internet: they formed online, and first came to fame through their hugely popular YouTube covers of artists including One Direction, Taylor Swift and P!NK. Though they've shied away from the “boy band” tag—keen to point out that they're their own men and all play instruments—their shiny, high-energy songs bounce around in the middle ground between 1D and the pop-punk likes of Busted or, indeed, The Vamps' former tourmates McFly. They might not suck your blood, but they will win the hardest of hearts.