GRIDKUSit down to a board game with your AI

In Sparring you play against your AI, and every move on the other side is your AI's own choice. Before you move, you can type something in the message box; your words reach your AI when your AI's turn comes, and your AI usually replies, then makes a move. In Challenge you and your AI sit on the same side against opponents in five ranks: Bronze, Silver, Gold, Platinum and Diamond. Each game has its own ladder: beat the highest-ranked opponent you've unlocked to open the next rank. Ranks you've unlocked stay open, so you can play them again any time. On your turn, tap “Ask for a hint” and your AI looks at the current position and gives you advice.

There's nothing to download. You play in the browser on a computer or phone, and you can play on your own. You do need to sign in with a Worldku account before you play.

You can play for free. Every account gets a weekly allowance that resets on Monday at 00:00 UTC. You can use more on the days you choose. Moves by the ranked opponents in Challenge and the greeting your AI may give you (at most once a day) don't use your allowance. Each turn your AI plays in Sparring, “Ask for a hint”, chatting with your AI and what your AI says after a match, Challenge matches included, use your allowance. Reading replies aloud and voice input use the same allowance. Your account shows the percentage of your weekly allowance remaining and a countdown to the reset. If it runs out, you can wait until Monday's reset or buy a top-up pack for extra allowance that never expires. Paid plans have a larger weekly allowance.

There's no clock, so take as long as you like. If you leave partway through, the match is kept. Back in the lobby, tap the game card marked “Resume” for a Sparring match; for a Challenge match, switch to Challenge, tap that game, then choose the rank marked “Resume”.

Yes. Besides replying to you, your AI may greet you when you sit down at a board, at most once a day, and may say a line or two after a match: some praise, a tease or a grumble. Turn on “Read replies aloud” in the message box to have chat replies read out. The greeting and the after-match lines aren't read out automatically; with “Read replies aloud” on, click the “Read aloud” button beside the message on a computer to hear them. If you haven't chosen a voice for your AI yet, a prompt appears with a link to choose one in Worldku.

With the same Worldku account, and depending on your memory settings, your AI can recall things you've talked about in other Worldku apps. The other way round, when your games come up in another Worldku app, your AI can check which games have a match in progress and at what move, plus how far you've climbed in Challenge in each game.