Orders for Apple's iPhone 4, which went on pre-order on June 15, topped 600,000 on the first day - a record for the group - resulting in a number of customers unable to order as Apple's servers buckled under the pressure. With handsets expected to be shipped to customers in the US and a select number of other countries towards the end of June, Apple has now pushed back shipping dates to mid-July for later online pre-orders. The iPhone 4 will then be rolled out to 88 countries by the end of September. No specific Middle East distribution date has yet been announced.