While it can be very useful to have say, a weather app on your smartphone that knows where you are when you want to find out current conditions for your location, does that mean that those apps should be able to know where you are even when you aren’t using the app? That’s a question raised by a new forthcoming study that found about dozen apps for Android smartphones are not only tracking where you are right now, but three minutes from now. And three minutes after that. And so on.

Computer scientists at Carnegie Mellon University found that dozens of popular Android apps collected device location (including GPS coordinates accurate to within 50 meters) an average of 6,200 times, or about every three minutes during a two-week study period, reports the Wall Street Journal.

Researchers recruited 23 users of Android’s version 4.3, with participants able to use their own choice of apps after installing software that logged app requests for a variety of personal information including contacts, call logs, calendar entries and camera output, along with location.

Even when an app provides a useful-location based service, some of those requested the data more often than would be needed to provide that service, researchers said.

For example: Groupon Inc’s app requested one participant’s coordinates 1,062 times in two weeks. Does Groupon need to know where you are? Sure, when you’re acvitely trying to find a deal. But the rest of the time…?

“Does Groupon really need to know where you are every 20 minutes?” asked Norman M. Sadeh, a Carnegie Mellon professor who co-wrote the study. “The person would have to be accessing Groupon in their sleep.”

In another part of the study, The Weather Channel’s app requested device location an average 2,000 times, or every 10 minutes during the study period. Which, unless you are really nervous about a storm ruining your outdoor party or an oncoming tornado, seems a bit excessive.

If you’re wondering, the research didn’t include comparable results from iOS users, because unlike Android which groups all its permissions for apps en masse — you can’t download an app if you don’t agree to all its permissions — iOS devices allow for users to adjust what data is collected by an app on an individual basis (click here for more on how to do so).

So I can have the Weather Channel app on my iPhone and turn the location data off (which isn’t that useful to me, but hey, I can do it).

It’s no secret why app developers want to cull as much location data as they can get, with marketers paying good money for online ads that can be targeted to individual users based on location information. That might mean an ad or a coupon for a retailer could pop up on the company’s app if it detects a user is nearby or even inside a store.

In previous research, Sadeh and his fellow researchers found that when an app is asking for your location, 73% of the time it shares that information with an advertising network. That’s something many people are likely not aware of when they give an app permission to access their location.

During the study, researchers found that when users were given a “privacy nudge” to tell them how many times apps collected their personal data each day, 95% of participants reported reassessing their app permissions and 58% chose to restrict apps from collecting data.

But should we have to be nudged?

“The defaults for location data are entirely backward. That data should only be revealed at a particular moment for a particular purpose. Instead, devices routinely reveal location, leaving the user subject to constant tracking,” Marc Rotenberg, president of the privacy advocacy group, the Electronic Privacy Information Center told the WSJ.

Apps Track Users—Once Every 3 Minutes [Wall Street Journal]

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