Apple's new iOS 5 operating is continuing to cause users a number of problems, two days after its initial release.
The free update, which brings over 200 new features - including iCloud - has proven to be so popular that Apple has struggled to keep up with demand.
A number of users have taken to Apple's forums to complain about iOS 5 taking a long time to download, requiring them to make a number of retries in an attempt to get it to work.
Others have also reported problems with text messages not sending,or apps - including Twitter and Facebook - not working once the new operating system was installed.
One user posted: "I just installed this new update and now my apps that were previously installed are not working. Mainly my banking apps."
Another said: "My friend has updated his iPhone 4 to iOS 5 and some of his apps including Facebook and Twitter aren't working. Tried re-syncing and turning off and on but still not working."
Ovum analyst Nick Dilson told Digital Spy that while bugs were a common side affect of any new software, the issues with iOS 5 seemed to be "on the serious scale."
He said: "There are a range of issues from people who can't get the update to load from content being deleted, applications going missing and, in the worst case scenario, phones bricking entirely."
One such customer, Brian Daynes, contacted BBC News to express his concerns were of a more serious nature than mere software bugs, saying: "Have got the error message 1611. When I contacted my provider Orange, they in turn contacted Apple, and were told that the 'Error 1611' is a hardware fault and is in no means related to the update process of iOS 5.
"On being told this, Orange want to now charge me £150 for a new iPhone. I am very upset over this, as I know full well that if I had not updated the phone, it would be in perfect working order today as I write this email."
Apple have yet to deal with any of the complaints.
For my personal iOS 5 experience, click here.
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