Apple has quietly launched a dedicated indoor positioning app on iOS, letting business owners map out their venues using just their iPhones. The Indoor Survey App was first spotted on the App Store by developer Steve Troughton-Smith, and although it doesn't appear in search, it's easily accessible via a direct link.

the app uses radio signals and Wi-Fi to locate users

"Enable indoor positioning within a venue using the Indoor Survey App," reads the description on iTunes. "By dropping 'points' on a map within the Survey App, you indicate your position within the venue as you walk through. As you do so, the Indoor Survey App measures the radio frequency (RF) signal data and combines it with an iPhone's sensor data."

Apple has been quietly building up its indoor mapping tools for years now. In 2013 it introduced iBeacons; small Bluetooth transmitters that retailers and venue owners can use to deliver location-specific notifications and alerts. And in last year's iOS 8 update, Apple gave developers access to more detailed location data using the iPhone's motion coprocessor. As noted by Apple Insider, the Indoor Survey App itself uses a combination Wi-Fi and radio signals to track positions — similar to technology developed by Silicon Valley startup WiFiSLAM, which Apple purchased for $20 million in 2013.

The login screen for Apple Maps Connect. (Apple)

Last October, Apple also launched Apple Maps Connect, which invited business owners to submit indoor mapping information. This wasn't for small corner shops though, with Apple specifying that participating venues must be accessible to the general public, offer Wi-Fi connectivity throughout, and attract more than one million visitors annually.

As of June last year, indoor positioning had been added for locations including the California Academy of Sciences in San Francisco and the Mineta San Jose International Airport, according to a report from 9to5Mac. It's possible that the Indoor Survey App could help expand this availability, making it easier, as the App Store description notes, for venue owners to collect data "without the need to install special hardware."