Zack Merrick, Alex Gaskarth and All Time Low - All Time Low perform at The O2 Arena in London on a joint tour with You Me At Six at The O2 Arena - London, United Kingdom - Saturday 14th February 2015 (1 Picture)
Zack Merrick, Alex Gaskarth and All Time Low
View All: All Time Low perform at The O2 arena
Next All Time Low Slideshow: All Time Low in concert - Glasgow Scotland United Kingdom - Thursday 12th February 2015
Perry appeared on James Corden's 'The Late Late Show' on Monday and addressed her long-standing rivalry with Swift.