Privacy Policy
Last updated October 25, 2026
This policy explains what personal information Stone.gs ("Stone.gs", "we", "us") collects when you use stone.gs, the Stone.gs apps for desktop, iPhone, iPad and Android, and related services, and what we do with it.
The short version
- You can play as a guest without giving us anything. An account needs only an email address and a username; we never store a password.
- Games you play are public unless you make them private, and your username, avatar and rank appear on them.
- We use Google Analytics to understand how the site is used, and we collect error reports and device details to keep the Go engine and site working.
- We do not sell your data, show ads, or share it for advertising.
- You can delete your account at any time from your profile.
Information we collect
We collect only what is needed to run games, rank players and keep the site working.
| Category | What it includes | Where it comes from |
|---|---|---|
| Account | Email address, username, chosen avatar (from our preset set), account creation date, role | You, at sign-up or in your profile |
| Rank and progress | Rank and rank history, provisional status, puzzle level and puzzle run scores | Your games and puzzles |
| Linked accounts | Google account ID; Apple ID identifier; OGS user ID, username, email and rank; Fox user ID, username and rank | Google, Apple or OGS, when you sign in with them; Fox, when you link it |
| Games | Moves, results, timestamps, time controls, visibility, and the username, avatar and rank of each player at the time | Games you play or create |
| Reports | Bug reports and puzzle reports you submit, with the app's recent log at that moment | You |
| Error reports | Error messages, page address, browser user agent, session ID, and your user ID and username if signed in | Your browser, automatically, when something breaks |
| Device and performance | Browser, CPU core count, memory, graphics card, screen size, language, and engine speed measurements | Your browser, automatically, to tune the Go engine |
Guests. Playing as a guest creates a random guest ID stored only in your browser. We keep no account record for guests, though their games and error reports are kept as described below.
What we don't collect. We do not store payment card details, your Google name or profile photo, precise location, or contacts. The site's own games have no chat.
IP addresses. Our servers see your IP address when you connect. We use it in memory to limit abuse, and it may appear in short-lived web server logs; we do not store it in our database.
Signing in and linked services
You sign in with an emailed code, with Google, with Apple, or with OGS.
- Email sign-in. We email you a one-time code or link. Codes expire after about two hours. If another player invites you to a game by email, we send you a sign-in link.
- Google. We ask Google for your email address and basic profile. We keep only your Google account ID and email address, and discard the rest.
- Apple. We ask Apple only for your email address, which may be an address Apple forwards to yours if you choose to hide it. We keep your Apple ID's identifier, that email address, and a token Apple issues us, which we revoke with Apple when you delete your account.
- Online-Go.com (OGS). Signing in with OGS lets you find and play OGS games from Stone.gs. We store your OGS user ID, username, verified email and rank. OGS access tokens stay in your browser so it can talk to OGS directly; our servers do not keep them. OGS games, including their chat, run on OGS. Read OGS's privacy policy.
-
Fox.
Stone.gs can sign in to Fox to play Fox games, from the Stone.gs apps or from the website,
and the two work differently.
In the Stone.gs apps. The app connects to Fox directly. Your Fox password is kept only in your device's keychain, as the hash Fox signs in with, and Stone.gs's servers never see your password or its hash.
On the website. A browser can't connect to Fox itself, so your games are played through our relay service, which signs in to Fox as you. To do that, we store your password's hash (never the password itself) and your Fox username in this site's storage in your browser (localStorage) until you sign out of Fox or unlink it.
If you link your Fox account to your profile, we store its Fox user ID, username and rank, and your browser reads your recent Fox games from Fox's public site to list them in My Games. Fox games, including their chat, run on Fox.
How we use your information
We use your information to run Stone.gs, and for nothing else. We don't use it for advertising, to send you spam, or sell it, and we won't share your information with any other parties unless the law requires us to, such as a valid court order or other binding legal request. If that happens, we will share only what the request requires.
What other people can see
Your username, avatar and rank are visible to anyone who sees a game you play. Your email address is never shown to other players.
- Public games. Anyone can watch them, including visitors who aren't signed in, while they are live and afterwards.
- Private games. Any signed-in player who has the link can open them.
We don't publish profile pages or make them crawlable to search engines.
How long we keep it
We keep account data while your account exists, and other data no longer than listed below.
| Data | How long |
|---|---|
| Account and puzzle progress | Until you delete your account |
| Games | Indefinitely |
| Error reports and bug reports | Up to 1 year |
| Device and performance data | Up to 2 years |
| Database backups | Up to 90 days |
Deleting your account. You can delete your account from your profile page. This permanently removes your account record and puzzle progress, and signs you out everywhere. Any games you are still playing against other people are resigned, and your open game listings are removed.
After deletion, your username is removed from all your past games. The games themselves stay in your opponents' histories, because they are shared records.
Children
Stone.gs is not directed at children under 13, and we don't knowingly collect personal information from them without parental consent. If you believe a child has given us personal information, contact us and we will delete it. Children can play as guests without providing any personal information.
Security
All traffic to Stone.gs is encrypted with HTTPS, and sign-in and invite emails are sent over TLS. Sign-in tokens are kept in your browser; signing out removes them from that browser, and deleting your account invalidates all of them.
Changes to this policy
We will post any changes on this page and update the date above. If a change materially affects how we use your information, we will tell you on the site before it takes effect.
Contact
This website is a personal, non-commercial hobby project. If you have any questions about this Privacy Policy or wish to request the removal of your data, please email us: stonegoserver@gmail.com