By the time you unsheath the phone wedged as tight as king arthur's sword in those skinny skorts masquerading as pants, tap tap to wake the device, swipe and select preferred app from among dozens across multiple screens, hum out a nursery rhyme as it loads, type and retype numerical figure (if you have Neanderthal thumbs like me)... yeah maybe just do some good old fashioned maths aye? Do you even Sudoku lol