An accessibility setting which adds icons to blocks to aid colour blind users.
Touch a block to select it, then touch another block of the same size to swap colours. The aim is to get one row all the same colour.
You can swipe up on a medium or large block to break it up into smaller blocks. Doing this will use an assist.
You start with 5 assists, every 1000 points you will get another assist.
Also every 1000 points, the time between a new row of blocks being added is reduced.