This Privacy Policy explains how MultiCards (“we”, “us”, “our”) collects,
uses, and protects your information when you use the MultiCards mobile
application (the “App”) — a collection of online multiplayer card games. By
creating an account or using the App, you agree to the practices described
here.
1. Information We Collect
Account information
Email address — used to create and sign in to your account.
Password — stored only in a securely hashed form by our authentication provider; we never see or store your plain‑text password.
Profile information
Username you choose (visible to other players in your games).
Avatar selection (a preset icon).
Game statistics such as games played, wins, and losses.
In‑app coin balance and the number of rewarded ads you have watched.
Gameplay information
Data needed to run the multiplayer games you join — for example your
in‑game hand, the shared game state, turn order, and the actions you take
during a match — across any of the card games offered in the App.
Game invite codes and lobby membership.
Push notification information
If you allow notifications, we register a push token for
your device — a unique identifier issued by your device's operating system
and obtained through Expo's push service — and store it with your profile
so we can alert you about your games (for example, when it is your turn or
a match has ended).
You can turn notifications off at any time from your device settings or
the app's profile screen; when you do, the token is removed from your profile.
Advertising information
The App offers optional rewarded video ads through
Google AdMob (“watch an ad to earn coins”). You are never
required to watch an ad to use the App.
When ads are served, Google's Mobile Ads SDK collects information such as
your device's advertising identifier (Android Advertising
ID or Apple IDFA), IP address, and general device and ad‑interaction data,
in order to show and measure ads and to detect invalid activity. Google
processes this data as an independent advertising provider under its own policies.
When you finish a rewarded ad, Google's servers notify our backend
(server‑side verification) using an identifier we generate for your account,
so we can credit the coins. The reward amount is fixed on our server; we do
not rely on any value sent from the device.
Basic technical data required to operate the service, such as connection
and request information processed by our backend to deliver real‑time gameplay.
Website (browser) — cookies and advertising
The App is also playable in a web browser. The browser version does not use
the Google AdMob SDK and does not offer rewarded video ads; instead it may
display Google AdSense advertising units on a small number of
non‑gameplay screens. Ads are never shown on a game table.
Strictly necessary storage. Signing in stores your session
in your browser's local storage. This is required for the site to work and is
not used for advertising.
Advertising cookies. When advertising is enabled, Google
and its partners may set cookies or read device and browsing information from
your browser to serve and measure ads. Google acts as an independent
advertising provider under its own policies.
Consent. If you are in the European Economic Area, the UK,
or Switzerland, we ask for your consent before advertising cookies are used,
through a Google‑certified consent management platform. You can change or
withdraw your choice at any time from the consent link on the site.
When no ads are shown, no advertising cookie is set and no
ad request is made. Advertising on the website can be switched off entirely,
and is off by default.
What we do not collect
We do not collect your precise location.
We do not access your contacts, photos, microphone, or camera.
We do not sell your personal data for money.
Apart from Google's advertising products described above — the AdMob
SDK in the mobile app, used only for optional rewarded ads, and AdSense on
the website — we do not embed third‑party analytics or tracking SDKs.
2. How We Use Your Information
Create and authenticate your account.
Run real‑time multiplayer games and keep game state in sync across players.
Show your username and avatar to other players in your games.
Track and display your game statistics.
Send you push notifications about your games, if you have enabled them.
Show rewarded video ads when you choose to watch one, and credit in‑app
coins for completed ads.
Show display advertising on the website, where permitted by your consent
choice. Website ads do not earn coins and are not tied to your account.
Operate the in‑app coin system. Coins are a virtual item with no monetary
value; they cannot be purchased or cashed out and are used only to create
games within the App.
Maintain the security and integrity of the service (e.g. preventing
cheating and invalid ad activity).
Respond to your support requests.
3. How Your Information Is Shared
We do not sell your personal information for money. Your information is shared
only as described below:
With other players: your username, avatar, card counts,
and public game actions are visible to other players in the same game. Your
private hand is never shown to opponents, and your email address, coin
balance, and ads‑watched count are never shown to other players.
Supabase — database, authentication, and real‑time
infrastructure used to store your data and operate the App on our behalf.
Expo (Expo Application Services) — app builds,
over‑the‑air updates, and push‑notification delivery. Your push token and
the contents of notifications pass through Expo's push service and on to
Apple (APNs) and Google (Firebase Cloud Messaging) to reach your device.
Google AdMob — serves the optional rewarded video ads
and processes advertising identifiers and device / ad‑interaction data as
an independent advertising provider.
Google AdSense — serves display advertising on the
website and processes cookie and browsing data as an independent advertising
provider. This applies to the browser version only.
Legal reasons: we may disclose information if required by
law or to protect the rights, safety, or security of our users or the service.
4. Data Retention
Account and profile data (including username, avatar, statistics, and
coin balance) is retained while your account is active.
Your push token is stored only while notifications are enabled and is
removed when you disable them.
Finished game records may be retained to maintain your statistics and game history.
Advertising identifiers and related data collected by Google AdMob are
retained and controlled by Google under its own policies.
When you delete your account, your personal data is deleted or anonymized
within a reasonable period, except where we must retain it to comply with
legal obligations.
5. Security
We take reasonable measures to protect your information, including encrypted
connections (HTTPS), hashed passwords, secure on‑device storage of your login
session, and access controls that prevent players from reading other players'
hidden cards. No method of transmission or storage is 100% secure, but we work
to safeguard your data.
6. Your Rights & Choices
You can:
Access or update your profile information from within the App.
Manage notifications — turn push notifications on or off
at any time from your device settings or the app's profile screen.
Manage ad tracking — reset or delete your device's
advertising identifier, or opt out of ad personalization, in your device
settings. You can use every part of the App without watching ads.
Manage advertising consent on the website — change or
withdraw the consent you gave for advertising cookies at any time, using the
consent link on the site.
Delete your account and associated personal data — see below.
Depending on your region (e.g. EEA/UK under GDPR, or California under CCPA),
request access to, correction of, or deletion of your personal data, and object
to certain processing.
Under some laws (for example, the California Consumer Privacy Act), sharing
advertising identifiers with Google to show rewarded ads may be treated as a
“sale” or “sharing” of personal information. You can opt out by not watching
rewarded ads and by limiting your device's advertising identifier as described above.
How to delete your account
You can request account deletion at any time by emailing
tanvirislam@ieee.org from your registered
email address. We will delete your account and associated personal data
(profile, statistics, coin balance, push token, and game participation) within 30 days.
7. Children's Privacy
The App is not directed to children under the age of 13 (or the minimum age
required in your country), and we do not knowingly collect personal information
from them. Rewarded ads shown in the App are served in accordance with Google's
policies. If you believe a child has provided us personal information, please
contact us at tanvirislam@ieee.org and we
will delete it.
8. International Data Transfers
Your information may be processed and stored on servers located outside your
country of residence. Where required, we take steps to ensure your data is
handled in accordance with this policy and applicable law.
9. Changes to This Policy
We may update this Privacy Policy from time to time. When we do, we will revise
the “Last updated” date above. Significant changes will be communicated through
the App or by other reasonable means. Your continued use of the App after an
update means you accept the revised policy.
10. Contact Us
If you have questions about this Privacy Policy or your data, contact us at: