The game of Stack has been implemented many times over the years and this UWP implementation looks professional and slick, with just one big caveat. The idea is sound - a casual game in which tiles slide in from different sides and you have to time taps to 'drop' them onto the growing stack. The kicker is that only the parts of the tile which match what's currently on the stack are allowed to stand. So misplaced taps mean a gradually reducing stack footprint on which to land your new tiles. And so on.
The pastel shades vary through the game, which is a nice touch. Tiles slide in from left and right/behind, though note that you don't have to drop them on pass one - you can let them bounce back and then have another go on in the opposite direction, etc.
The caveat mentioned above is that there's a small but finite delay between tapping to 'drop' a tile and it - it's repeatable and you get into the rhythm of it all quite quickly. But it's worth mentioning, since it'll drive you mad for the first five minutes! The game's also slow to launch, 15 seconds is surely too long for a casual game like this?
You can grab this here in the Store. My best was 20, by the way. It's funded by banner ads, and there doesn't seem to be a way of removing them, sadly.