Privacy

Short version: your games are saved on this server. Nothing is stored on your device, and nothing is shared with anyone else, until you allow it.

If you allow it, this site keeps a random id in your browser. It is not a name, an account or an address. All it can tell me is whether ten games were played by ten people or by one person ten times.

Nothing is stored until you say yes. If you say no, the site works just as well: your games are still saved, they just cannot be recognised as belonging to the same player. That costs me a statistic and costs you nothing.

If you say yes, Google Analytics also sets two cookies, called _ga and _ga_HQ87G8YVVN. These count visits. They last up to two years, though many browsers shorten that.

Two things are stored whether you say yes or no: your answer to this question, and the colourblind setting if you switch it on. They remember choices you have made and nothing else.

You can undo either answer at any time by clearing this site's data in your browser; the question comes back on your next visit.

When you play, the moves are saved on this server along with the difficulty you chose, which side the coin gave you, how the game ended, and how long you spent on each move. That record is how anyone can tell whether the game is worth playing, including where people stop playing.

No IP address is stored in a game record. That is deliberate and it will stay that way.

If you send feedback, what you wrote is saved along with which game you were playing, how far it had got and how it ended. That context matters, because the same sentence means different things after a win and after giving up on move twelve.

Your email address is optional and is only there so I can reply. It goes on no list and is used for nothing else. If you leave it blank, there is nothing in the feedback to identify you.

The web server keeps an access log for two weeks and then deletes it. It records the IP address of each request and the page that was asked for.

While you are playing, the page address includes the game's id, and the player number if you allowed one. The log therefore connects an IP address to a game for those two weeks. I use it only to check whether the site is being attacked.

The typefaces, stylesheets and scripts are served from this site. Opening a page makes no request to any other company, unless you have said yes to counting visits.

I use Google Analytics to count visits. It loads only if you say yes. If you say no, the code is never fetched.

It collects the pages you visit, how you got here, your screen size and language, and roughly where in the world you are. Your IP address is used to work out that last one and is not stored. The data is held on Google's European servers, and I do not allow Google to use it for advertising. Google keeps the visit data for two months and the returning-visitor data for fourteen months.

The signup form on the front page is run by Kit, an email company in the United States, because that is how the list is sent. If you enter your email address it is stored by them. It is used only to send those updates.