Conserving power on iPhone | iLounge Article


Conserving power on iPhone

Ask iLounge offers readers the opportunity to get answers to their iPod-, iPhone-, iPad-, iTunes-, or Apple TV-related questions from a member of the iLounge editorial team. We'll answer several questions here each week, and of course, you can always get help with more immediate concerns from the iLounge Discussion Forums. Submit your questions for consideration using our Ask iLounge Submit Form. We reserve the right to edit questions for grammar, spelling, and length.

View the complete Ask iLounge archives...

Q: I assume that the boot up process on the iPhone uses more energy than when the phone is in sleep or Airplane mode. Let’s say you need to periodically check your iPhone for email or voicemail, but don’t need to know immediately if either of these things happen. At what point does it pay to turn your iPhone off and on, as opposed to putting it into Airplane/sleep mode, to maximize your battery life?

- Tom

A: For the most part, leaving the iPhone in Airplane Mode and otherwise sleeping with the screen off will significantly reduce battery drain. The main source of power consumption on the iPhone is the cellular and Wi-Fi radios and the iPhone screen itself.

While turning the iPhone off entirely will obviously consume even less battery, the difference in battery consumption compared to sleeping the iPhone in Airplane mode is relatively small. Further, although the startup process will consume some additional power, this is also fairly minimal, although obviously higher than simply putting the iPhone to sleep in Airplane mode.

Another important consideration is the time it takes to wait for your iPhone to boot back up after powering it off. Considering that powering off the iPhone entirely doesn’t result in any significant reduction in power consumption versus simply putting it to sleep in Airplane mode, it’s probably not worth the additional wait time when you want to actually use your iPhone.

Keep in mind that the iPhone can easily get more than 24 hours of audio playback time on a full charge, even with the cellular and Wi-Fi radios turned on. Further, our tests with the iPhone 3G have actually shown playback time in excess of 29 hours while in Airplane mode. Without audio playback, the iPhone could remain sleeping in normal mode for a couple of days, and would last in Airplane mode even longer.

Note that you should always return your iPhone to the home screen before putting it to sleep. Some applications will consume power even when the iPhone is in sleep mode and Airplane mode. One such example is the iPhone Camera app, which keeps the camera powered on even when the device has gone to sleep. Leaving the Camera app running can drain your battery very quickly even when you’re in Airplane mode and have other power-draining features turned off.

« Syncing Apps on new iPod touch

Syncing new iPhone »

Related Stories

iLounge Weekly

Recent News

Recent Reviews

Recent Articles

Sign up for the iLounge Weekly Newsletter

iLounge is an independent resource for all things iPod, iPhone, iPad, and beyond.
iPod, iPhone, iPad, iTunes, Apple TV, Mac, and the Apple logo are trademarks of Apple Inc.
iLounge is © 2001 - 2018 iLounge, Inc. All Rights Reserved. Terms of Use | Privacy Policy