On Tuesday, we told you that a number of Apple iPhone owners have been experiencing problems with the iMessage application ever since they updated their handset to iOS 7; messages are not being sent out and some that re sent are not being received in a timely fashion. Some messages are being received hours later, sometimes with a batch of other messages that were sent earlier in the day...
Source: http://www.phonearena.com/news/Apple-to-send-out-iOS-update-to-fix-iMessage-bug_id47905
Source: http://www.phonearena.com/news/Apple-to-send-out-iOS-update-to-fix-iMessage-bug_id47905