We’re very intrigued by augmented reality technology (AR for short) which gets you to point your smartphone or tablet’s camera at something in the real world to make digital stuff happen on-screen.

Here’s a new example of AR being used for a children’s app: The Tortoise and the Hare by developer Zientia, which tells the familiar tale of a slow tortoise beating a fast-but-arrogant hare in a race a modern reworking.

The app, available for iPhone, iPad and Android, actually starts with you printing out the two main characters, from a PDF file downloaded from Zientia’s website.

Your children can then colour it in using whatever colours they like. You then point your device at the finished pictures to see the hare and tortoise – complete with the colours that your children have chosen – appear in full 3D.

“Children venture into a world of dreams and animation, discovering the fable in a personalised way through a drawing they have coloured in,” suggests the developer in the app store listing. “The drawing comes alive and the children become the protagonists, taking part in the action and the story.”

The Tortoise and the Hare is one of a number of AR apps we’ve seen for children over the last year or two: others focused on colouring include colAR Mix, where you colour in printouts then watch animated versions of those objects, and SquiggleFish, where kids draw fish and other sealife then scan them into a virtual aquarium.

We’ve also seen more educational apps using AR technology, such as Our Discovery Island – a phonics game from Pearson Education – and Big Bird’s Words from Sesame Street, which sends kids off round the house scanning words on grocery products as a way to practise their reading.

The Tortoise and the Hare is a free download for iPhone and iPad from Apple’s App Store, and also a free download for Android from the Google Play store. It’s a try-before-you-buy deal, so (on iOS at least) an in-app purchase of £1.49 unlocks the whole thing.