It's awfully easy to run out of mobile phone power when you travel. The travel industry has offloaded lots of activity and paperwork to the smartphone in your pocket: Flight check-in, fee collection, boarding passes, and arranging the ride to the airport are often handled on passengers' devices, leaving us with depleted batteries for the flight.
Once passengers board, many airlines continue draining power by forcing flyers to use phones or tablets to make purchases or watch in-flight entertainment.
Lest we run completely out of juice before landing, thus running the risk of not being able to navigate the last leg of the journey or tell loved ones we have arrived, many of us top up smartphone batteries at the gate before boarding.
For that purpose, many airports and lounges provide some free USB ports (never enough to serve the hundreds of waiting passengers, and far too many of the charging stations are broken, but those are separate issues).
We're sure you've used the USB ports. We all have.
Well, now the FBI says don't.
A warning about public USB charging stations
Last week, the FBI's Denver office, which happens to be near one of the most lavish modern airports in the country, tweeted the following warning, which speaks for itself:
"Avoid using free charging stations in airports, hotels or shopping centers. Bad actors have figured out ways to use public USB ports to introduce malware and monitoring software onto devices."
That's right. Because we can't have nice things anymore, villains are altering those ports to hack into phones, help themselves, and mess up your entire life. Techies call it juice jacking.
The FBI recommends this as an alternative to USB charging ports: "Carry your own charger and USB cord and use an electrical outlet instead."
That applies whether or not you've connected to the free Wi-Fi signals you find, which represent yet another giant digital scam waiting to happen.
Note that the FBI's admonition only applies to USB ports, which, if you aren't sure, are the ones with flat plugs, pictured above. You can still use a regular electrical socket with an appropriate charging cord because electrical outlets aren't a threat to transmit data to your phone. (Standard electrical outlets tend to charge faster, anyway.)
"While this isn’t the first time we’ve heard official government organizations warn about juice jacking, this is the first time we’ve heard any of them say we should avoid public USB outlets altogether," wrote Android Authority, which tracks smartphone security.
Alternatives to public USB charging portsThe FAA says American passengers may carry up to two lithium ion batteries that are powerful enough to charge a phone, provided they only store up to 101–160 watt hours (Wh) per unit and they're in your carry-on, never checked.
Just remember to bring the cord that works for you. (Here's a battery that's good for several uses without recharging.)
Outside of the United States, particularly in Europe, some airlines may place tighter restrictions on the power of the external battery you're allowed to bring aboard, so make sure you know the limit for your flight before you go.