Effective 5 August 2026
RustChap is designed to work entirely on your device. By default, it collects no data and sends nothing anywhere.
Your puzzle progress, attempts, tutor conversations, and settings are stored only on your iPhone. The optional profile fields (name, email) are stored on your device and are not transmitted; RustChap operates without any server.
By default the tutor runs on-device using Apple's Foundation Models. Nothing you type leaves your phone.
If you choose to enable the OpenRouter option and enter your own API key, your tutor messages (and the puzzle context they reference) are sent to OpenRouter under OpenRouter's privacy policy, using your key and account. This is off by default, and you can turn it off or remove the key at any time in the profile screen. The key is stored in the iOS Keychain on your device.
No analytics, no advertising, no tracking, no third-party SDKs, no account creation.
If this policy changes, the updated version will be published at this address. Questions: open an issue at github.com/unclecode/rustchap.