Spades

Yes. No account, no download and no limit on games. If ads ever appear to keep the site running, they'll stay off the table.

The player across the table from you, at the top of the screen. Your partner always plays the strong way. The two players on your left and right (West and East) are your opponents; Settings lets you make them strong or easy.

Yes, with up to three friends. Tap Play a friend, then pick a friend or the computer for each of the other three chairs: your partner across the table, West and East. Each friend gets their own link to open, sent by text, email or chat, and the cards are dealt once everyone's in. The computer plays any chair you leave to it. Each of you only ever receives your own cards. If someone closes the page, opening it again picks up the same game. A friend game with no moves for 14 days is deleted.

The strong player bids by counting its likely tricks: high spades, long spades, side aces and kings, and short suits it can trump. It bids nil only with a hand that has almost no high cards, covers a partner's nil, dodges bags once its side has made its bid, and tries to set the other side when it can. It remembers every card played and who has run out of which suit. In our test, strong partners beat easy ones in 938 of 1,000 games. None of the computer players ever looks at another hand.

Tricks you take over your bid. Each one adds a point, which sounds nice, but once your side has 10 of them you lose 100 points and the count starts again. The scorecard on the table shows each side's bags. In 2,000 games between four strong computer players, a side lost 100 to bags 0.67 times per game on average.

Nil, yes, any time: tap Nil on the bid panel. Blind nil (bidding nil before you look at your cards, worth 200) is a setting, and like the rules on pagat.com it's only open to a side that's 100 or more points behind. After a blind nil you may swap two cards with your partner.

No. Once a card is on the table, everyone has seen it, so taking it back would be like peeking. To stop slips of the finger, a card takes two taps to play: one to pick it up and one to play it. If you'd like one tap instead, turn it on in Settings.

Yes. During the play it marks the card the strong computer would play and says why, like "your partner is already winning this trick." You get 6 hints per game, and asking again about the same move doesn't use another one. The suggested bid on the bid panel is always free.

Yes. Settings has a game to 300 instead of 500. In our test games between strong players, a game to 500 took 10.61 hands on average and a game to 300 took 5.89.