Terms of use

The app

Castlei is a chess practice app for Android. We grant you a personal, non-exclusive, non-transferable right to install and use it on devices you own or control, for your own non-commercial use, subject to these terms and to the licenses of the open-source components described below.

Accounts

An account is optional and is only needed for cloud backup. You are responsible for your Google account and for activity under it. Provide accurate information and tell us if you suspect unauthorised use.

Cloud backup

Cloud backup is provided on a best-effort basis to help you restore your games on a new device. It may be interrupted, limited or changed. It is not a guarantee that your data will always be available, so please also keep an exported backup file (Settings → Export backup file). We may remove accounts or backups that are abused, or that stay inactive for a long period after reasonable notice where we can reach you.

Castlei Plus

Castlei Plus is an optional one-time purchase made through Google Play that unlocks the features described in the app and on our website, currently automatic cloud backup and a longer backup history. Prices and availability are shown in the store before you buy. Payments, taxes, refunds and cancellations are handled by Google Play under its terms; we do not process your payment. The purchase is tied to your Google account and is not transferable. We may change what Castlei Plus includes, but we will not remove features you have already paid for without a fair alternative or refund.

Acceptable use

Do not misuse the app or the services behind it. In particular do not attempt to break or overload our services or other users' access, reverse engineer the cloud features to bypass limits or security rules, use the app unlawfully, or upload content that is unlawful or infringes others' rights. Nothing here restricts the rights you have under the open-source licenses of the open-source components.

Your content

Your games, studies, comments and other content stay yours. We receive a backup of it only if you use cloud backup, and only use it to provide that backup and restore it to you. We do not review or use it for any other purpose.

Chess analysis

The engine, evaluations, move labels, opening names and puzzle solutions are tools to help you learn. Engine strength settings are not human ratings and are not an official rating. Analysis can be wrong or incomplete, and results depend on your device and the time given.

Open-source software and trademarks

Castlei includes open-source software, including the Stockfish chess engine and the dartchess library (GPL-3.0), the Lichess puzzle and opening data (CC0), the Fraunces typeface (SIL Open Font License) and many other packages, each under its own license. The notices are in the app under Settings → About → Open-source software. These terms do not limit any rights you have under those licenses. Source code for the GPL-licensed components is available on request at andwatiian@gmail.com.

The Castlei name, logo and original artwork are our trademarks and property. The licenses above do not give you the right to use them, for example to name a modified version of the app.

Third-party services

The app relies on services from Google (Firebase, Google Play, Sign in with Google). Your use of them is also subject to their terms and privacy policies.

No warranty

The app and services are provided “as is” and “as available”. To the extent the law allows, we do not give any warranty that the app will be uninterrupted or error-free, or fit for a particular purpose. Nothing in these terms excludes warranties or rights you have under mandatory consumer law where you live.

Limits on liability

To the extent the law allows, we are not liable for indirect or consequential losses, lost data or lost profits arising from your use of the app. Our total liability for any claim relating to the app is limited to the amount you paid us for it (if anything) in the twelve months before the claim. Nothing in these terms limits liability that cannot be limited by law, including liability for death or personal injury caused by negligence or for fraud.

Ending

You can stop using the app at any time by uninstalling it and, if you wish, deleting your account (see Delete your account). We may suspend or end access to cloud features if you break these terms or to protect the service.

Changes

We may update these terms. The effective date above shows the latest version, and we will tell you in the app about significant changes. If you keep using the app after a change takes effect, you accept the updated terms.

Law

These terms are interpreted according to the law that applies to them where you live, and they do not take away any mandatory consumer rights you have there. If part of the terms cannot be enforced, the rest still applies.

Contact

Ian Andwati
andwatiian@gmail.com