PUBLISHED: 10:43 EST, 26 April 2013 | UPDATED: 12:26 EST, 26 April 2013 Customers around the world who pre-ordered Samsung's Galaxy S4 handset so they could have one on the day it is released face delays of up to a week. UK operators were today forced to send messages to customers after Samsung blamed 'unprecedented demand' for the Android handset. US customers were also being warned of delays. The Galaxy S4 goes on sale around the world this weekend - but Samsung has admitted it has not been able to keep up with demand, leaving customers who ordered weeks ago facing delays
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Handset set to take on Apple's iPhone 5 - and some experts say it could even outsell it
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Shortages reported around the world for flagship Android handset
'The Samsung Galaxy S4 can be a game changer for @placeholder, and I believe for the first time that this device has the potential to outsell the next generation of iPhone - assuming that Apple will incrementally improve the next version of the iPhone.'