Smartphone location tracking has become a hot topic over the past few days, after a report emerged last week claiming iPhones and iPads are quietly recording users' locations and saving the data to unencrypted files. Later it was clarified that the company is simply mapping nearby Wi-Fi hotspots and cell towers, as opposed to your exact location, and is doing so using anonymized data when users opt-in to their iOS device's location services.

Other mobile platforms such as Google's Android access location data much in the same way. But while that in itself may be nothing new, particularly if you choose to use location-based services, the fact that companies are collecting and storing this info in ways users aren't always aware of has prompted authorities to start asking questions.

Republican lawmakers in the US sent letters to six companies asking them about how their products collect, store and relay information about users' locations. The letters included questions on whether or not they hand on data to third parties, if users were notified of data tracking and if they are given the opportunity to opt-out.

Although Google and Apple are particularly in the spotlight due to the recent reports, the inquiry from the U.S. House Energy and Commerce Committee also involves Microsoft, Nokia, Research In Motion and HP -- all of which have smartphone operating systems on the market. What's more, the reports have already prompted investigations by regulators in France, Germany, Italy and South Korea according to Business Week.

"We provide users with notice and control over the collection, sharing and use of location in order to provide a better mobile experience on Android devices," reads a statement from the search giant. "Any location data that is sent back to Google location servers is anonymized and is not tied or traceable to a specific user."

Apple hasn't officially commented on the matter but, unsurprisingly, lawsuits were quick to hit the company. The plaintiffs in a Florida case, Vikram Ajjampur and William Devito, accuse Apple of violating privacy laws, as well as the Computer Fraud and Abuse Act, by keeping a log of user locations without offering a way to disable the feature. The suit seeks a judge's order to bar the alleged data collection, along with punitive damages and a refund for the devices.