One Direction, iTunes Festival, Roundhouse, London, review

One Direction performing at the iTunes Festival at the Roundhouse in Camden. Photo: AP

They've earned £100 million since coming third on The X Factor two years ago, becoming one of the most commercially successful British groups of all time.

The five likely lads that make up One Direction – Liam Payne, Harry Styles, Louis Tomlinson, Niall Horan and Zayn Malik – now have their own range of dolls, are the new faces of Pepsi, and have a movie on the horizon. So far, so one-dimensional. But where Take That, Boyzone and Westlife failed, One Direction have triumphed: in America. When their debut album topped the US charts in its first week, these teenagers achieved something that no other British band – including the Beatles – has ever managed.

What’s fascinating about them is that they appeal to both young girls and older women. Their knowing nods to the genre’s clichés – a tongue-in-cheek sidestep here, a playful fist clench there – are undeniably charming. Floppy-haired Harry is already a renowned “cougar hunter” having dated presenter Caroline Flack, 15 years his senior. And judging by the mixed crowd that came to Thursday’s gig at the Roundhouse in Chalk Farm (part of the month-long iTunes festival), the boys are keeping up with their dual image: kiddy pop with a touch of promiscuity.

The concert was the last of their Up All Night tour, which seems to have taken its toll as the group appeared tired for much of the first half, plodding through mediocre ballads Gotta Be You and I Wish. The shrillness of screaming girls, possibly whipped up into hysteria by Harry’s preposterously skinny jeans, eventually seemed to shake them up for rousing performances of hits including the synth-drenched Everything About You, the gloriously catchy What Makes You Beautiful and a credible cover of the Kings of Leon’s rocky Use Somebody.

The stage was transformed first into a beach party, then a giant snow scene. The most illuminating part, however, was an interval in which the lads took to Twitter to answer questions sent in by admirers, harnessing the power of the medium that made them. Fervent fans delighted with an hour and a half of guitar-heavy pop were rewarded with drumsticks given out by the Niall (the “cute” one) and autographs signed mid-set by Louis (the “spontaneous” one).

Next year the band will embark on a global tour. If they stick to the bouncy, upbeat anthems at which they excel, they are likely to conquer the world further.