About Stack Up

A block slides back and forth above your tower. Tap to drop it. The part that lands on the block below stays; whatever hangs over the edge is sliced off and tumbles away — and the next block is only as wide as what was kept. Miss the tower altogether and it's over.

Drop a block within a hair of perfectly in line and it snaps into place with nothing lost. Three perfect drops in a row and the block grows wider again, so a steady rhythm can rebuild a tower that was getting thin. The blocks speed up as the tower climbs, and each one comes in from its own side at its own pace.

The daily tower is the same for everyone — the same blocks, the same sides, the same speeds — and is scored a point a block, two for each perfect drop. Free play deals a new tower every time.

Tips to win

• Watch the block below, not the one moving
• Tap a touch early: the block keeps moving while your finger lands
• Chase perfect drops when the block is narrow — three in a row widen it
• Find a rhythm; the speed changes a little from block to block