What it teaches
The order of the alphabet, which a child needs long before they need it for a dictionary — it is the backbone every other letter task hangs on.
The letters are spoken by name: ay, bee, see. Some browser voices say "capital C" when handed a bare letter, which tells a child about a distinction the game does not offer, so the names are spelled out instead.
How it works
Letters appear and the child puts them in order. The keyboard has one case, so there is no choice to make between C and c and no reason to mention it.
A letter in the wrong place is not accepted and goes back, and the round does not move on until it is right.
What to look for
This is the first game to try with a child who is five. It asks nothing about reading and nothing about meaning — only about order.