Brainblox is played with eight coloured blox. If colours are hard to tell apart, you can show a letter on each one: G green, B blue, R red, Y yellow. The letters stay upright whichever way a blox is turned.
The same switch sits at the bottom of the How to play panel inside every game. Your choice is remembered on this device.
Other ways to play
Everything can be done by tapping: tap a blox, tap the box to place it, and use the Turn, Put back and Empty box buttons under the box.
On a computer you can use the keyboard instead: R to turn, Esc to put back, arrow keys to nudge a selected blox and Delete to take it out.