Boasting 200 new features, the free software update has proven to be so popular that the firm's servers have struggled to cope with demand.
Taking to internet forums, Apple users complained that the download was taking an unreasonable length of time.
Some consumers, in fact, said that they had to try to download it many times.
"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 worse case scenario phones bricking entirely," explained Nick Dillion, an analyst at Ovum.
Earlier this week, users of Facebook's long-awaited iPad app started reporting minor bugs.
Facebook conceded that there were some bugs, but explained that it was not unusual for new products.
Posted by Andre Dixon
