By Nathan Barton

Both Mike and “Slave Larry” make some excellent observations about privacy, tracking, and stores – and as Mama Liberty pointed out, all the others who can use that data being collected. (see the commentary “Cashless society and privacy.”

Larry, there are several ways that your friend could have gotten that message from Dollar General.  They are not all totally invasive of privacy, but they can be.

First, she probably had the DG app on her phone.  In installing that app, almost certainly she voluntarily allowed them to collect her location data – that is, to track her whereabouts.  It may have been Bluetooth that connected: it may also have been the store’s wifi hotspot.  (More on that in a moment.)

If she didn’t have the DG app, she very well may have had her phone set to automatically detect and connect to a wifi hotspot, like more and more stores have. Again, that is an option she can select (or turn off), which is designed to improve reception, save data usage, and – frankly – share info that can be mined from your phone.

Many people LIKE having their phone find and instantly connect to a wifi hotspot.  As Mama points out, people do some incredibly stupid things today.  Twitter, Facebook, Instagram, and even business sites like Linked-in are filled with the detritus of people’s lives.  But you don’t HAVE to voluntarily give up that information – and you can work to make it at least harder for the security-goons and used-car salesmen from getting all that info.

All of these things (DG app, Bluetooth, and wifi) are in her control: she can disable the wifi-seeking and linking, or allow linking only with her approval each time.  She can, as was pointed out, turn off Bluetooth.  She can also use security in Bluetooth to deny connecting to any other device without her approval each time. She can simply uninstall the DG app. And likely, there is an option in the DG app that lets her accept or reject instant messages (and coupon offers).

(If she loves DG so much, then at least just use their on-line website to get coupons, and keep her phone info out.)

Of course, she can just leave her phone in her car – even turn it off and drop it in a metal ammo box or other Faraday cage device to cut off its signal. There is nothing sinful about not having instant contact to the rest of the world for a half-hour.  (Those of us who travel in remote locations without cellular service live with that all the time.)

While Mama doesn’t use a smartphone, many of us find that the smartphone is incredibly useful for our work, business, and family lives.  So we don’t want to give up the technology.

What can we do to keep our privacy, or at least some of it?

First off, consider the advantage of burner phones and airtime cards bought for cash (as long as we can still use cash, of course).  There are frequently very good bargains – a basic flip phone can often be had for as little as $10, and though minutes can be pricy compared to modern unlimited plans (remember the days of 10 and 25 cents/minute), there are also often discounts of 50-75% on “base rates.”  Or, for a higher price, consider a burner smartphone for web and data.  Although it requires a bit of juggling and self-discipline, you can regularly (or irregularly) rotate those phones, and by using services like Google Voice, even have a common, long-term phone number to give people who need to know.

Whatever you do, when you are NOT using a phone, pull the battery AND put it in a Faraday cage (which can be a bag or many other things).  You can buy a small bag (8″x8″) for under $7, and a 16″x8″ bag for under $9.  Or use an insulated lunch bag with a double layer of heavy-duty aluminum foil.  Or a metal ammo can.  Be sure and test whatever you buy or build, to make sure that it really is blocking the signal.

Key is to remember that we DO still have some control, as Mama points out.  We can best keep our private information private by not sharing it.  If you MUST have that particular store’s preferred customer card for discounts (and discounts for “members” can sometimes be as much as 50-60% on a shopping cart full of purchases), you can use Google voice (or many other services) for the phone data.  You can usually use a post-office box instead of a street address (with an annual fee, of course), and in many rural areas, you can even get a street postal address by just buying and putting a mailbox up on a convenient location (with permission of the landowner, of course).

It gets tougher as time goes on, so think seriously about what you can do now, to prepare for later.