This is a “waiting for the bus” or “stuck in a queue” kind of casual game. Stack (iOS, Android) is an exceedingly pretty and minimalistic game with soothing background music (as is fashionable these days) that requires short bursts of concentration.
The idea is to tap on coloured rectangles as they whizz past, stopped them in time to land upon the previous rectangle in perfect alignment.
Should you misalign, the overlapping part of the shape falls away, whittling the incoming rectangles down to nothing as the stack rises.
It sounds a bit pointless but you’ll find yourself wanting to beat the previous stack score.
Each time you slot the shape in correctly, it plays a note of the scales and once you align eight in a row, you’re rewarded with an extra bit of rectangle back.
itunes.apple.com/ us/app/stack/id1080487957?mt=8