"Some of you may already have been informed via email [by Apple], but for those of you that haven't, I can assure you that Apple is trying to get to the bottom of this problem," a user identified as 'mikefradette' said on Apple's official iPhone forum.
"Let's just say they have selected a beta group to help solve this issue."
Others reported that technical support representatives had asked them to install Apple software that logs application usage and power consumption. Apple technical support has also used an 11-item questionnaire in its discussions with users in an attempt to figure out the cause of rapid battery drain, including questions are about Wi-Fi, Bluetooth and email use.
"There's still no smoking gun," said Aaron Vronko, the CEO of US-based Rapid Repair, an iPhone repair shop.
"But the processor in the iPhone 3GS can use 50 percent more power in some situations than its predecessor. I'd bet that Apple missed some key interactions between the iPhone's software and the processor in the last update that causes it to over-utilise the CPU, especially since [the complaints] came after the software update."
Vronko was referring to the iPhone 3.1 update that Apple shipped two weeks ago.
Most of the users with problems on the Apple support forum who identified their iPhone's model said they were using the 3GS, although some said they had seen battery life drop off on their iPhone 3G smartphones as well.
In fact, complaints about battery consumption started in June, when Apple rolled out the iPhone 3.0 software.
The clamor grew even louder after users installed iPhone 3.1, and shows no sign of abating. One thread on the topic, which debuted on September 10, has more than 570 individual posts, and has been read by over 40,000 people, an extremely high number for Apple's forum.
"I'm glad this is an actual problem. I thought I was just going crazy," said iPhil. "After [iPhone] 3.1, battery sometimes doesn't even last an entire day with no additional talk than I had using 3.0."
"The day after I installed the 3.1 firmware, everything changed. I have to charge the iPhone in the middle of the day to be able to have enough battery to get home," added ‘help with iPhone'.
"I think this is exactly the kind of thing you'd see from an unexpected software interaction with the processor," argued Vronko today.
But Apple's doing the right thing by asking iPhone owners how they're using their smartphones, and requesting that some install logging software.
"Some of these [people] are probably heavy application users, though they may think they're light users," said Vronko. "But [the logging software] is likely looking not just at the applications being used and the power consumption, but recording down to the last processing thread what's occurring."
Vronko was optimistic that Apple would get to the root of the problem. "Diagnostics like that should make it pretty easy for them to narrow it down," he said.
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