There are plenty of mapping apps available on the market, including Google Maps, Nokia Maps, and even Apple's own much-maligned pre-loaded Maps app in iPads, iPhones and iPod Touch devices.
But Ordnance Survey says the unique selling point of its mapping app is the accuracy of its Great Britain maps, as they have been produced using a team of 250 surveyors and two aircraft making over 10,000 changes to the mapping database every day.
Following the recent criticisms over accuracy that beset Apple Maps, including some entire UK towns being absent from the maps, Ordnance Survey feels it is a "trusted" source for people navigating around Britain.
The OS MapFinder app on iOS devices is aimed mainly at "outdoor enthusiasts", offering a free overview map for the whole of Great Britain. However, after downloading the app users have to pay to access more detailed map data for specific areas.
Sections of mapping data are purchased in single 10km-by-10km tiles, with prices starting at 69p each. This brings Ordnance Survey's recognised print quality to iOS devices using 660 dpi, meaning the maps appear sharp and clear on Apple's Retina screen.
All maps are cached on the device so they can be used even without a WiFi or mobile 3G signal. Users can search for locations by place name, postcode, or Ordnance Survey Grid reference.
Walking, cycling or running routes can be recorded on the device and then reviewed or repeated at a later date, including options to personalise the routes with photography.
Peter ter Haar, the director of products at Ordnance Survey, said that the agency "prides itself on generating accurate and up-to-date mapping data".
"Customers will now be able to enjoy the same experience as using a trusted Ordnance Survey paper map when exploring Great Britain on the go, at the touch of a screen," he said.
"OS MapFinder is an extension of our outdoor products with accessibility to our quality mapping in print, online and now on mobile devices."
The OS MapFinder app is available to download now from iTunes.
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