Editing Privacy (section)

===Privacy and location-based services===
{{main|Location-based service}}

Increasingly, mobile devices facilitate [[geolocation|location tracking]].  This creates user privacy problems.  A user's location and preferences constitute [[personal information]], and their improper use violates that user's privacy.  A recent MIT study by de Montjoye et al. showed that four spatio-temporal points constituting approximate places and times are enough to uniquely identify 95% of 1.5M people in a mobility database. The study further shows that these constraints hold even when the resolution of the dataset is low. Therefore, even coarse or blurred datasets confer little privacy protection.<ref>{{cite journal |last=de Montjoye|first=Yves-Alexandre|author2=César A. Hidalgo |author3=Michel Verleysen |author4=Vincent D. Blondel |title=Unique in the Crowd: The privacy bounds of human mobility|journal=Scientific Reports|date=March 25, 2013 |volume=3| page=1376|doi=10.1038/srep01376|pmid=23524645|pmc=3607247|bibcode=2013NatSR...3.1376D}}</ref>

Several methods to protect user privacy in location-based services have been proposed, including the use of anonymizing servers and blurring of information. Methods to quantify privacy have also been proposed, to calculate the equilibrium between the benefit of obtaining accurate location information and the risks of breaching an individual's privacy.<ref>Athanasios S. Voulodimos and Charalampos Z. Patrikakis, "Quantifying Privacy in Terms of Entropy for Context Aware Services", special issue of the Identity in the Information Society journal, "Identity Management in Grid and SOA", Springer, vol. 2, no 2, December 2009</ref>

====Ethical controversies over location privacy====
There have been scandals regarding location privacy. One instance was the scandal concerning [[AccuWeather]], where it was revealed that AccuWeather was selling locational data. This consisted of a user's locational data, even if they opted out within Accuweather, which tracked users' location. Accuweather sold this data to Reveal Mobile, a company that monetizes data related to a user's location.<ref>{{Cite web|last=Whittaker|first=Zack|title=AccuWeather caught sending user location data – even when location sharing is off|url=https://www.zdnet.com/article/accuweather-caught-sending-geo-location-data-even-when-denied-access/ |date=Aug 22, 2017 |access-date=2021-11-22|website=ZDNet|language=en}}</ref>  Other international cases are similar to the Accuweather case. In 2017, a leaky API inside the McDelivery App exposed private data, which consisted of home addresses, of 2.2 million users.<ref>{{Cite web|date=March 20, 2017|first=Jeremy|last=Kirk|title=McShame: McDonald's API Leaks Data for 2.2 Million Users|url=https://www.bankinfosecurity.com/blogs/mcshame-mcdonalds-api-leaks-data-for-22-million-users-p-2426|access-date=2021-11-22|website=BankInfoSecurity|language=en}}</ref>

In the wake of these types of scandals, many large American technology companies such as Google, Apple, and Facebook have been subjected to hearings and pressure under the U.S. legislative system. In 2011, US Senator [[Al Franken]] wrote an open letter to [[Steve Jobs]], noting the ability of [[iPhones]] and [[iPads]] to record and store users' locations in unencrypted files.<ref>Popkin, Helen A.S., [https://archive.today/20120714202126/http://technolog.msnbc.msn.com/_news/2011/04/21/6508416-govt-officials-want-answers-to-secret-iphone-tracking "Government officials want answers to secret iPhone tracking"]. MSNBC, "Technolog", April 21, 2011</ref><ref>{{cite web|title=Apple faces questions from Congress about iPhone tracking|website=[[Computerworld]]|url=https://www.computerworld.com/article/2507868/apple-faces-questions-from-congress-about-iphone-tracking.html |first1=Gregg |last1=Keizer |date=2011-04-21|archive-url=https://web.archive.org/web/20190720044451/https://www.computerworld.com/article/2507868/apple-faces-questions-from-congress-about-iphone-tracking.html|archive-date=2019-07-20|url-status=live}}</ref> Apple claimed this was an unintentional [[software bug]], but Justin Brookman of the [[Center for Democracy and Technology]] directly challenged that portrayal, stating "I'm glad that they are fixing what they call bugs, but I take exception with their strong denial that they track users."<ref>{{cite web|title=Apple denies tracking iPhone users, but promises changes|website=[[Computerworld]]|url=https://www.computerworld.com/article/2506250/apple-denies-tracking-iphone-users--but-promises-changes.html |first1=Gregg |last1=Keizer |date=2011-04-27|archive-url=https://web.archive.org/web/20230329094239/https://www.computerworld.com/article/2506250/apple-denies-tracking-iphone-users--but-promises-changes.html|archive-date=2023-03-29|url-status=live}}</ref> In 2021, the U.S. state of Arizona found in a court case that Google misled its users and stored the location of users regardless of their location settings.<ref name="state-arizona-redacted-complaint">{{cite web|url=https://www.azag.gov/sites/default/files/2021-05/Complaint%20%28redacted%29.pdf|title=Complaint for Injunctive and Other Relief|access-date=2021-06-03|date=2021-06-03|publisher=The Superior Court of the State of Arizona In and For the County of Maricopa}}</ref>