I'm not a massive gamer; I was pretty addicted to Tetris on my brother's Gameboy in 1991, I've dabbled with Angry Birds and I've bought quite a few first person shooter games over the years for my Dad, but a friend at work showed me this game app - and it is absolutely amazing.

Monument Valley is beautiful, with elegant graphics, a delightful soundtrack that reminds me of Bagpuss or The Clangers crossed with a soothing spa treatment and homages to Escher sprinkled throughout. On several occasions, when I'd worked out the Princess' journey, I audibly gasped at the cleverness. My friend's 4 year old boy loved it too (and probably completed it quicker).