Apple isn't alone in tracking the location of its iPhone customers -- it turns out if you use an Android phone, Google is keeping an eye on you, too.
The news that the iPhone secretly tracks its users' location data came to light April 20 and set off a firestorm of privacy-related controversy from security experts and academic researchers all the way up to Capitol Hill.
Initially, experts said the data was stored only on the iPhone and Apple didn't collect it. But according to the Wall Street Journal, Apple does collect the location logs. And Apple is not alone: Google receives location data about its phone users at least several times an hour.
Android phones transmit to Google the names, locations and signal strengths of nearby Wi-Fi networks, security researcher Samy Kamkar told the Journal.
Why are Google and Apple tracking you?
Citing the research firm Gartner, Inc., the Journal wrote that Google and Apple are tracking their phone users' location data to "tap the $2.9 billion market for location-based services -- expected to rise to $8.3 billion in 2014."
Location-based services allow companies to more specifically target customers by region, and can help advertisers and marketers hit you with specific ads based on where you live.
Google has previously said it uses location logs to help compile databases of Internet Wi-Fi hotspots, which can help cell networks better route calls and build traffic maps.
This is not the first time Google has come under fire keeping close tabs on you.
Last October, Google admitted that its Street View cars mistakenly harvested emails and passwords from residents' Wi-Fi networks in dozens of countries.