Apple chief executive Steve Jobs says the company knew its iPhone 4 would lose signal when held a certain way, but did not think it would be a big issue.

Jobs said Apple is “working our butts off” to solve “Antennagate”. Each owner of an iPhone 4 is to get a free rubberised case called a Bumper, which tackles the issue, and those who already bought one will get a refund, Jobs said. Customers can return their iPhone 4 for a full refund within 30 days.