Privacy Policy

Updated: 15 September 2026

This policy covers Aicos Chess and this support website. The operator is Minh Cao, an individual. Contact: mjnkao@gmail.com.

Data and purposes

On your device: offline games, settings, and Energy balances/usage records are stored to resume play and manage access. Computer move calculations run on the device. Local data may be included in device backups according to operating-system settings.
When you sign in: Apple or Google and Firebase Authentication process account identifiers, sign-in provider information, and the name and email shared by the provider to authenticate you and display your account. You can play offline without creating an account.
Online play: the service stores player identifiers, rooms, moves, game state/results, timestamps, request records, and rate limits to operate and synchronize games and prevent abuse. The other player in your room can receive game data and participant identifiers; room data is not a public directory.
Service connections: the app may fetch configuration and check its version when connected, even if you only use offline play. Services and SDKs process IP addresses, app/SDK version information, and technical request information to provide, secure, and maintain the service. Sign-in providers may use IP addresses to estimate a general location for fraud prevention.
Invitation QR scanning: if you choose to scan a friend’s invitation, the app requests camera access and reads the QR code on your device. The app does not store or upload camera images for this feature. The decoded invitation is used to join the online room. You can enter an invitation code or link instead of using the camera.
Support: if you email us, we receive your email address and the content you provide to handle your request.

Sign-in and technical SDK data

Google Sign-In declares that it may process account and device identifiers, contact information (including a phone number where available to the provider), approximate location, usage information, and other technical data for sign-in functionality and service analytics. Firebase Authentication and Firestore also declare technical diagnostic data for analytics. These provider disclosures do not mean that Aicos Chess asks you to enter a phone number. The app does not use these SDKs for targeted advertising.

Providers and sharing

The app uses Apple/Google for sign-in and Google Firebase/Google Cloud for authentication, databases, and online functions. This website is hosted on GitHub Pages; GitHub processes connection information under its own policy. Providers may process data outside your country.

We do not use this data for targeted advertising or sell personal data. Data is processed to operate and protect the service and support users, and may be disclosed when required by law.

Retention and deletion

Local data remains on your device until removed; platform settings govern backups. Account data remains in the authentication service until the account is deleted. Online data is retained to operate and resume games; room expiration does not mean the record has been deleted. The current version does not apply a universal automatic deletion schedule to online data, rate-limit records, and deletion confirmations. Providers retain technical logs and backups under their policies. Support emails are retained to resolve and follow up on requests; you can request deletion by email.

In version 0.11.2 and later, open the account screen and choose “Request account deletion”. The app sends your account identifier, account email and sign-in provider, contact email, reason, request identifier, status, and request/deadline timestamps to the service so we can verify and process your request. Requests are processed manually within 30 days, and confirmation is sent to your contact email. Submitting a request does not immediately delete data. The request concerns your Aicos Chess account and associated data; it does not automatically delete accounts in other games, your Apple/Google account, or offline games on your device.

Earlier versions provide “Delete Aicos Chess data”, which removes some game data and signs you out but does not delete the shared authentication account. To request deletion of the remaining account or ask for access or correction, contact mjnkao@gmail.com. We may verify ownership before acting. Data required for legal obligations or the protection of legal rights may be retained. Deletion requests and processing records are retained to handle and document the request; there is currently no universal automatic retention schedule for these records.

Children and policy changes

Children can play offline without providing account information. Parents or guardians may contact us about a child's data.