Five Republican lawmakers from the House Energy and Commerce Committee have asked Apple, Google and four other tech companies about how their devices track and share users’ location data.

In letters sent to Apple, Google, Microsoft, Nokia, Research In Motion and HP on Monday, representatives Fred Upton (R-Mich.), Greg Walden (R-Ore.), Lee Terry (R-Neb.), Mary Bono Mack (R-Calif.) and Marsha Blackburn (R-Tenn.) questioned the companies’ use of their users’ location data.

The lawmakers want to know what location data is collected; why the data is collected; where it’s stored; and whether consumers can opt-out of having their information collected, among other questions. The companies have until May 9 to respond.

The letters from members of the House GOP were issued on the same day Senator Al Franken (D-Minn.) announced he was holding a hearing on mobile technology and privacy. Both Apple and Google have been invited to the May 10 hearing, which will include testimony from the Department of Justice and the Federal Trade Commission.

Illinois Attorney General Lisa Madigan also has called for a meeting with Apple and Google about how their devices collect and store users’ location data.

The letters come amid recent reports that Apple’s iOS and Google’s Android operating systems are tracking and storing detailed logs of users’ location.

According to a report last week from independent researchers Alasdair Allan and Pete Warden, the iPhone records detailed location data about its user and then transfers that information to the user’s computer when they sync their device to iTunes. Android-based smartphones reportedly also store and share information about users’ location.

Google declined to comment specifically on the letter, but said in a statement that users can opt out of location sharing on Android devices.

“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,” the company said. “Any location data that is sent back to Google location servers is anonymized [sic] and is not tied or traceable to a specific user.”

Nokia defended how its devices used users’ location data and said users had “several” opt-out options when using the company’s location service.

“No related personal data is intended to be permanently stored in the device or by Nokia, unless Nokia has obtained user consent for collection and use of personal data,” the company said in a statement.

Microsoft could not provide a statement by press time. Apple, Research In Motion and HP did not reply to requests for comment.