Lessons of Sandy: How to keep your phone juiced longer

Question: How can I keep my phone running as long as possible during a natural disaster like Sandy?

Answer: For all the grief that the wireless carriers get for dropping calls in ordinary circumstances, they've earned a lot of credit this week for keeping some service intact even as Hurricane Sandy punched the lights out up and down the Northeast Corridor.

You can't guarantee that the carriers' under-recognized efforts to build more resilient systems and back up their towers with batteries and standby generators will overcome the next super-storm -- they still lost as much as 20 percent of their cell sites in New York this week. But a few steps will maximize your chances of getting useful information and staying in touch with the outside world over surviving wireless networks.

The most important one among them is having an external charger that can replenish a phone's battery multiple times, yet is light enough to carry to the nearest working outlet. Most of you already own one: a laptop computer.

HOW TO DONATE TO OPERATION SANDY RELIEF

Keep a laptop plugged in when idle at home - or at least do that once the weather forecasts turn foreboding - and you can recharge your phone by plugging it into one of its USB ports. On some models, you may need to wake the laptop to get power flowing to the phone, but you should then be able to close the computer's screen as the mobile device continues to recharge.

It also helps to keep a few extra cables for your phone handy. Any new Android phone will take a standard micro-USB cable (buy generic models online to save money); 30-pin dock-connector cables for older iPhones are also widely available, but that's not the case with Apple's new Lightning cable. Having a travel-sized power strip may also help avoid conflict when you find only one outlet open at a coffee shop, convenience store, generator or even another power strip.

Next, remember how to set your phone to sip power. The simplest way to do this is to disable as many of its built-in transmitters as possible: GPS, Wi-Fi and Bluetooth are all expendable when you only need mobile broadband service.

In Android, you can often shut off all three with a power-control widget available by swiping down from the top of the screen; if not, open the Settings app and look under its wireless and location headings. In iOS, you can disable Wi-Fi and Bluetooth from the Settings app's main menu; in iOS 5, you can also kill GPS under the Location Services heading, but in iOS 6 you need to select the Privacy category to see that option.

(If you know of a reliable Wi-Fi source near you -- perhaps one of the access points Comcast has made free to all in Sandy-swamped markets -- you can turn Wi-Fi back on when you're near it. Otherwise, avoid the slight battery drain caused by the phone checking for signals.)

Then crank your phone's screen all the way down by disabling its auto-brightness option and dimming its backlight as low as possible: hit the Display category in Android's Settings app or the Brightness or Brightness & Wallpaper heading in iOS, depending on your version. The screen will be hard to read in daylight, but who cares when the lights are out at home?

You can also disable the automatic data syncing that many apps perform in the background -- but it may be simpler to keep your phone in airplane mode and then take it online every hour or every few hours to see what's new.

(In a weird way, my experience nursing smartphones along at crowded, battery-killing tech events like CES turned out to be good training for the 40 hours my family and I spent without power, which is nothing compared to what friends in New York and New Jersey are still going through).

Tip: Your phone may also be an FM radio

What if you have no Internet access at all? If you own an Android phone, it may include an FM radio tuner that you can use to receive updates during an emergency. Several Motorola and Samsung models, among others, ship with this feature; to tune in, plug in a headphone cable (which doubles as an antenna) and scan around in that app until you find a news station.

USA Today