You’ve probably heard about the growing phenomenon of the adult colouring book. No, that’s not some kind of weird X-rated colouring between the lines – just straightforward colouring-in books being marketed not for kids, but specifically for adults.

The whole thing seems to have started in France where publishers started promoting colouring-in books as a stress-busting activity for adults. And blimey it took off! By the end of last year, colouring books were out-selling cookery books in France.

In the UK booksellers are reporting rocketing sales with colouring books representing half of the best-sellers on Amazon, including number 1 best-seller Secret Garden by illustrator Johanna Basford - described as ‘an inky treasure hunt and colouring book’. 

And meanwhile, on the other side of the globe, another new craze is emerging - in Australia adults gather for 'colouring circles' in coffee shops, where they sit in silence, fastidiously staying inside the lines," says The Times. 

So what’s behind this sudden desire to put down the iPhone, step away from the iPad, and pick up a good old-fashioned analogue drawing instrument? Johanna Basford reckons it’s partly about rediscovering the joy of doing something off-screen, something that isn't digital, and partly about trying to tap into our inner creativity which somehow got buried as we grew up. “Everyone is creative deep down but as you get older you get less confident in your abilities.”

The Guardian’s Philippa Perry says it’s about freeing your mind and learning how to play again, while Matt Cain, also in the Guardian, says colouring-in is way too much fun to be left to children and that, as adults, we enjoy the nostalgia and the relaxation it brings. 

For a perfect mix of nostalgia and relaxation, with a touch of subversion thrown in, why not try a bit of eatsleepdoodle colouring in – the doodle tablecloth has an all-over graph-paper design which you can choose just to colour-in, or to doodle your own designs as you get more adventurous. Or on a smaller scale, the doodle placemat to go has the graph paper print one-side and a placemat setting on the other, all ready for playful grown-up doodling, and the doodle pencil case has some printed shapes for you to colour in AND, when you’ve finished, it’s the perfect place to keep your pens too!