Some iPhone 4S owners are still having issues with battery life and some are reporting issues with contacts, despite the recent iOS 5.0.1 update.

"The recent iOS software update addressed many of the battery issues that some customers experienced on their iOS 5 devices,” Apple said in a statement to AllThingsD. “We continue to investigate a few remaining issues.”

Apple released the update yesterday, after testing it with end users and developers in the past couple of weeks. Apparently, they didn't test it enough because now the company is headed back to the drawing board.

"It seems like the major issue where people's batteries were draining at about 10% an hour on standby have largely disappeared," user robhoward88 writes in the Apple Support forum. "However, my issue has not been solved! Since I've had my iPhone 4S the battery has been a problem. It hasn't been draining at warp speed but it is definitely going down faster than it should, like 1% an hour on standby. Much quicker with usage, 1% every few minutes of browsing."

He continues, "My iPhone runs warm-ish and is definitely not putting in the performance advertised by Apple. 200 hours standby? No way. 6 hours of video? Not a chance. If I got an hour of video out of it I'd be surprised."

Another user, fatfergus, writes on the Apple forum that the update made his battery worse.

"I was just about to embark on deploying 100 iPhone 4S units in our company but I have just put a halt to it as there is no way that our users will tolerate such poor battery life," he writes. "Apple had better come up with a fix and pretty darn quickly."

Users have also complained about the update screwing up contact information.

"My iPhone could no longer remember the names of any of my contacts!" Paul Hontz wrote on the Startup Foundry. "I opened up the contacts app on my phone and discovered that all of entries were still there but if I got a text or a call my iPhone would have a sudden bout of amnesia and forget the contacts name."

It seems that iOS 5 has been cursed since its launch where users ended up with bricked phones, experienced activation issues and more.

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