Apple's iOS 5.0.1 seems to have created a glitch with the Contacts app for certain users, according to various sources and several posts on the Apple Support Forums.
Startup Foundry founder Paul Hontz reported late last week that after updating to 5.0.1, the iPhone was no longer able to associate address book contacts with other apps. Opening the Contacts app would display all the right names. But using the iMessage texting app or even making a phone call would fail to remember the name of a contact and just display the person's phone number.
Hontz tweeted about this potential bug and said he heard back from others who ran into similar issues. A search of the Apple Support Forums also revealed several people complaining of the same problem.
Apparently, the glitch pops up only under certain conditions.
You must have a Verizon iPhone 4S (Hontz said he received no reports from iPhone 4 users) and you must have updated to iOS 5.0.1 using the OTA (over-the-air) method rather than installing it through iTunes on your computer. I have a Verizon iPhone 4S but I updated it via iTunes and have seen no problems with my contacts.
Disabling and renabling iCloud contacts didn't fix the glitch for Hontz, but he did list some steps provided by one of his readers, which are detailed at his Web site. (Note: the site has been very slow to load.) Likewise, tech site Redmond Pie also offered a few suggestions to try to resolve the problem.
Rolled out Thursday, iOS 5.0.1 was supposed to fix a variety of bugs, including the notorious battery drain issue. Responses have been mixed as to whether the update fixed the battery problem, had no effect, or made it worse, though Apple revealed on Friday that it was continuing to investigate a "few remaining issues" with the battery.
With ongoing reports of the quick battery drain and this Contacts glitch, Apple may already be busy cooking up iOS 5.0.2 in the labs as it struggles to squash these persistent bugs.
Apple did not immediately respond to CNET's request for comment.