How to castle

To castle, your king or rook can't move before you do it. To castle, make sure there are not any pieces between your king and rook. Tap the king and select the furthest dot to the direction you want to castle. This is what it might look like.:

Or this.:

It can also be a combination of both, like this.:

Or this.:

Now you know how to castle!

(The notation for a king's side castle is O-O, and for a queen's side castle, it is O-O-O)