Apple has launched an app to allow people to map out a place’s interior, and it did so mostly without telling anyone.

A new link has appeared within the app store to an app called Indoor Survey. But it can’t be found through a normal search — requiring a direct link — and can only be used by people with a specially registered account.

The app appears to be part of Apple’s plans to bring more maps to the indoors. Apple has been gradually rolling out new ways of providing mapping information inside buildings, and the new app seems to be a way of making use of that.

The app allows people to walk through a building and droop “points”, which can then be used as a way of getting around venues. The phone measures its distance from Wi-Fi and radio signals, presumably using technology from a very similar company that it acquired in 2013.

"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."

The app could be a part of Apple’s plans for MapsConnect. That service allows businesses to add themselves to Apple’s Maps data, or change the data that’s on there.

Apple’s moves into indoor mapping have also included iBeacons. Those are little Bluetooth transmitters that allow phones to know precisely where they are, and allow app makers to send out specific notifications depending on locations.

In pictures: iPhone 6s goes on sale Show all 10 1 /10 In pictures: iPhone 6s goes on sale In pictures: iPhone 6s goes on sale Despite the rain, some 40 on-line reservation buyers visit the Apple Store in Omotesando neighborhood as the iPhones new models - iPhone 6s and iPhone 6s Plus go on sale in Tokyo, Japan Rex In pictures: iPhone 6s goes on sale Sam Shaikh holds up two bags containing the new iPhone as he is surrounded by store staff after the release and sale start of the new Apple IPhone 6S at the Apple store in Covent Garden, London In pictures: iPhone 6s goes on sale Apple fans pose for selfie at the store in Australia, during the launch of the new iPhone 6s In pictures: iPhone 6s goes on sale People cheer at the launch of the new iPhone 6s, at the store in Australia In pictures: iPhone 6s goes on sale 19-years-old David Kiss from Debrecen, Hungary, shows off his new iPhone 6s at the Apple store in Munich, Germany. Kiss camped in front of the shop for almost a week to be the first to get the new smartphone In pictures: iPhone 6s goes on sale A customer tries out a rose gold iPhone 6s Plus smartphone at the Apple Store near the West Lake in Hangzhou city, Zhejiang province, China In pictures: iPhone 6s goes on sale A member of staff processes a transaction as customer purchase phones during the launch of the Apple iPhone 6s at The Apple Store Opera, in Paris, France In pictures: iPhone 6s goes on sale The Apple store in Beijing launches the new iPhone 6s In pictures: iPhone 6s goes on sale Veronika Babochkina, 27, from Moscow, Russia, looks at the new iPhone 6s at The Apple Store in Opera, after queuing for few days, in Paris In pictures: iPhone 6s goes on sale Jonathan Pierrard, 26, from Rossignol, Belgium is the first customer to leave with the new iPhone 6s at The Apple Store in Opera, after queuing for few days, in Parisr to open new shortcuts - a feature Apple calls 3D Touch. (AP Photo/Francois Mori)