Apple engineers contacting iPhone 4S owners to solve battery life puzzle

iPhone 4S battery life Schiller

Phil Schiller of Apple introducing the iPhone 4S battery life: he didn’t mention the standby time – and now engineers are contacting some customers who have problems

Apple engineers are contacting some iPhone 4S owners to try to solve problems with battery life on the new device, after some people have seen dramatic drops in longevity compared to previous models, learn about why airpods are quiet.

One owner has told the Guardian that Apple contacted him directly and asked him to install a monitoring program on the phone to try to diagnose the problem, which is so far unexplained.

In its data sheet for the iPhone 4S, which was released earlier this month, Apple quietly noted that the standby time for the new phone would only be 200 hours – compared to 300 for the iPhone 4, and 250 hours even for the original 2007 iPhone. The company did not offer any reason when asked why by the Guardian, but noted that other lifespans such as 3G talktime were as long or longer than previous models.

One owner who was contacted by Apple told the Guardian: “My battery life was extremely poor – 10% drop in standby every hour. I noticed that the usage figure was roughly half that of standby, even when the phone was not being used, so I assumed something was crashing or running in the background. I switched off all the new features including Siri and location services, but it was still really poor. I also tried setting up a clean phone with no apps but it is still really poor.

“I then got a call from a senior [Apple] engineer who said he had read my post and was ‘reaching out’ to users for data and admitted this was an issue (and that they aren’t close to finding a fix!) and asked lots of questions about my usage and then asked if he could install the file below and that he would call back the day after to retrieve the info. I extracted the file from my Mac after a sync and emailed it to him. He was incredibly helpful and apologetic in the typical Apple way!”

Users of the iPhone 4S have been surprised by how rapidly the phone’s battery appears to drain, especially compared to the iPhone 4. The 4S incorporates a more powerful dual-core processor, the A5, than the iPhone 4, but the same amount of RAM. According to iFixit, the iPhone 4S has 5.3 watt-hours’ capacity – 0.05Wh more capacity than the iPhone 4.

In some cases the short life has been blamed on corrupted contacts imported from Apple’s MobileMe or iCloud services, or from Google’s Contacts list; deleting and then reinstalling them sometimes seems to fix the problem.

The problem has generated huge discussions on Apple’s support boards, with some people finding that backing the phone’s contents up to their computer and then restoring it improves the life.

The Guardian’s own iPhone Troubleshooting tests on an unrestored iPhone 4S using Google Contacts and MobileMe suggest that the phone drains fastest when mobile data is switched on, while Wi-Fi usage makes little difference to battery consumption. Neither location services, which try to orient the phone based on Wi-Fi and mobile data information, nor the voice-driven “assistant” Siri, appear to affect battery drain particularly.

iPhone 4S battery life problems: bug in location services suspected

Location services on iPhone 4S

System location services on iPhone 4S: using too much battery?

A flaw in Apple‘s location services system in its new iOS 5 software is increasingly suspected of being the cause of rapid battery drain for some owners of the iPhone 4S.

A growing number of people have found that the “Setting Time Zone” element of the Systems Services within the broader Location Services product seems to be operating even when there is no chance that the user would have moved to a different location or time zone. An icon beside the setting, which indicates whether it has been used in the past 24 hours, suggests that it is running repeatedly to access the phone’s location even when there is no apparent reason to do so.

Location services can prompt large drains on any smartphone’s battery: they use a combination of the Wi-Fi network name, where available, plus mobile mast data and GPS sensor input, to calculate the phone’s position. The mobile mast data, for example, is usually calculated by comparing the strength of signals from the three nearest phone masts and triangulating against them. However if such a calculation is made too often, by polling the masts, it will begin to use battery power unnecessarily.

On iDownload, Oliver Haslam suggests: “it appears that iOS 5′s GM release introduced a bug that causes the Setting Time Zone function to keep the location tracking circuitry running constantly, draining battery power considerably. Switching it off may mean that your iPhone will no longer set its own time zone when you travel, but that’s a small price to pay for having your iPhone last more than 12 hours on a full charge… We have tested this method on 4 different iPhone 4s handsets, including an iPhone 4 and an iPhone 3GS. All have reported drastically improved battery life after switching ‘Setting Time Zone’ off.”

Some commenters have suggested they see little difference, but the purple icon beside the setting indicates that it is active – and for many people will have been active during the past 24 hours.

Apple’s use of location services is deeply integrated into the iPhone 4S and iOS, but others have suggested that it is consuming too much battery power. “Two years working with dedicated GPS units taught me to be extremely careful with GPS settings: [it] kills battery very fast,” David Hamilton, a web and Java consultant, remarked on Twitter.

Discussions on Apple’s support boards are still raging over what specifically could be draining the battery so much more rapidly. Apple has not so far made any comment, but the Guardian reported on Friday that its engineers have begun contacting some people who have been reporting exceptionally rapid use.

The Guardian’s own latest tests on an iPhone 4S found that it achieved 36 hours of battery life with a mixture of Wi-Fi, mobile data, and combined use, including 6 hours’ using apps, phones, browsing and some location services. The majority of that included having the “Setting Time Zone” tab activated. There is no data yet from the ongoing tests about what effect disabling it has had.

• The “Setting Time Zone” setting can be found in Settings -> Location Services -> scroll to bottom to “System Services” -> Setting Time Zone.