Cardslot
Privacy Policy
Last updated: 2026-08-14
1. Introduction and data controller
Cardslot is a mobile application that tracks prices and promotions of games sold on the European Nintendo eShop and
can notify you when a game you follow changes price. It is developed and operated by Aurélien Ribon, an individual
developer (entrepreneur individuel) trading under the brand "Auline" ("we", "our" or "us"). We are the data
controller for the personal data processed through the app. This Privacy Policy explains what data we collect, why
we collect it, on which legal basis, who receives it, where it is hosted, how long it is kept, and what rights you
have over it. It is written to comply with the EU General Data Protection Regulation (GDPR). You can reach us at any
time at contact@cardslot.app, and our postal address is provided free of charge on request at that same address.
2. Data we collect
2.1. No account, no name, no email address
Cardslot has no user accounts. We do not ask for, and do not collect, your name, your email address, your postal
address, your phone number or your date of birth. You do not sign up and you do not sign in. The only identifier
attached to the data described below is the installation identifier explained in the next section.
2.2. Installation identifier ("icode")
When the app is first launched, it generates a random identifier called an "icode" (for example
p-1a2b3c4d). It is generated on your device, it is not derived from any hardware, account or
advertising identifier, and it is not an advertising identifier. It is sent with every request the app makes to our
server, and it is used as the key under which your data is stored on our server and as the customer identifier
passed to our purchase provider (see section 4). It remains the same for as long as the app stays installed on your
device. If you uninstall and reinstall the app, a new identifier is generated, unless your device restores a backup
of the app, in which case the previous identifier comes back along with the rest of the local data (see section
2.9). Under the GDPR this identifier is treated as personal data, because it allows us to single out one
installation.
2.3. Your watchlist (the games you follow)
The list of games you follow is stored on your device and is also sent to and stored on our server, so that it can
be restored and so that price alerts can be computed for you. What is stored is a list of Nintendo game identifiers
with the date at which each entry was added or removed. It is stored under your installation identifier only, with
no name or email attached.
2.4. Push registration data
If you allow notifications, the app sends us the push token issued by Apple or Google for your device, together with
the platform (iOS or Android), the language of the app interface and your device's time zone (for example
Europe/Paris). The time zone is used so that notifications are sent at a reasonable local hour rather
than in the middle of the night, and the language so that they are written in yours. This data is stored on our
server under your installation identifier and is overwritten each time the app starts.
2.5. Alert preferences
Your alert preferences — which of the two kinds of alert you want to receive — are kept on your device and sent to
our server, under your installation identifier, so that what we send matches what you asked for. They are two
switches and nothing else: no target price, no schedule, no profile. Both only ever concern a game you chose to
follow, and both are on by default; you can turn either off in the app at any time.
2.6. Purchase status
Cardslot offers a one-time in-app purchase that unlocks the full version. Payment itself is handled entirely by the
Apple App Store or Google Play: we never see and never receive your payment card, your billing address or your store
account. What we store on our server is a flag indicating that the installation has been unlocked, and the date at
which it was unlocked. To verify that a purchase is genuine, our server queries our purchase provider RevenueCat
using your installation identifier. RevenueCat is also contacted every time the app starts on iOS and Android, not
only when you buy: the app registers your installation identifier with RevenueCat at launch in order to know whether
this installation has already been unlocked and to display the current price. RevenueCat therefore receives your
installation identifier, and the technical device and store data its software collects, even if you never make a
purchase.
2.7. Technical request data and server logs
Every request the app makes to our server carries, in addition to the installation identifier, the app build number,
the platform (iOS, Android or web) and the two-letter language code of the app interface. For the purposes of
operating, debugging and protecting the service against abuse, our server writes log records containing this
information together with the address of the request that was made. Because a game page is requested by its
identifier, these logs show which game pages have been opened by a given installation, and when. They are not linked
to any name or email address, they are never used to build a profile or to measure your behaviour for commercial
purposes, and they are automatically deleted 30 days after they are written.
2.8. Failed-search reports
When a search returns no result, the app offers you a button to report it. If, and only if, you press that button,
the text you searched for (truncated to 120 characters) and your interface language are sent to us, together with
your installation identifier as with every request, and appear in our server logs, so that we can find out what is
missing from our catalogue. This report is not stored in our database, it disappears with the logs after 30 days,
and it is never sent automatically: nothing about your searches leaves your device unless you press that button.
2.9. Data that stays on your device
Your settings (interface language, platform filter, sorting, minimum discount and similar preferences), the local
copy of your watchlist and the downloaded catalogue of games and prices are stored in the app's own storage on your
device. Application logs produced by the app are written to the device console only and are not transmitted to us.
Uninstalling the app removes this local data from your device; see section 7 for what happens to the data held on
our server. The backup mechanism of your operating system (Google on Android, iCloud on iOS) may copy this local
storage and restore it when you reinstall the app, in which case the installation carries on with the same
identifier and the same watchlist. Those backups are performed by Google or Apple, under the backup settings of your
device, and not by us.
2.10. IP addresses
Like any service reachable over the internet, our server necessarily receives the IP address of the connection. Our
application code does not store IP addresses in its database and does not write them to its own logs; an IP address
may be used transiently in memory to apply rate limits. The reverse proxy standing in front of our server writes
standard access logs containing the IP address, the date and the address of the request; they are not linked to your
installation identifier, serve only security and abuse prevention, and are deleted after 14 days. Loading game
artwork and screenshots, and opening an eShop link, connects your device directly to Nintendo's servers, which
therefore receive your IP address (see section 5).
2.11. Storage on your device
The app writes to its own storage only what is strictly necessary to provide the service you asked for: the
installation identifier, your settings, your watchlist and the downloaded catalogue. These operations are exempt
from the consent requirement of Article 82 of the French Data Protection Act (Article 5(3) of the ePrivacy
Directive), which is why the app asks you for no storage consent. Apart from the technical information described in
this policy, the app reads no other information from your device, uses no cookie for advertising or measurement
purposes, and does not access the advertising identifier of your device.
3. Purposes and legal bases
We process the data described above for the following purposes, on the following legal bases under Article 6 of the
GDPR:
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Providing the service you asked for (storing and restoring your watchlist, computing price alerts, unlocking the
full version after a purchase): performance of a contract, Article 6(1)(b).
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Sending push notifications about the games you follow: your consent, Article 6(1)(a), given through the
notification permission of your operating system, which you can withdraw at any time in your device settings.
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Keeping the service running, diagnosing errors, and protecting it against abuse, scraping and denial of service
(technical logs, rate limits, counters): our legitimate interest in operating a secure and available service,
Article 6(1)(f).
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Improving the catalogue from the failed-search reports you choose to send: our legitimate interest in improving
the service, Article 6(1)(f), triggered only by your explicit action.
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Verifying purchases and preventing fraudulent unlocks: performance of a contract and our legitimate interest,
Articles 6(1)(b) and 6(1)(f).
We do not use your data for advertising, profiling or automated decision-making producing legal effects. The
contract referred to above is the Terms of Service of the app, published at /terms.html.
Providing the installation identifier is necessary to use the app: every request our app makes to our server carries
it, and the app cannot work without it. Everything else is optional: the app works without notifications, no
failed-search report is ever sent unless you press the button, and if you follow no game, no watchlist is stored on
our server.
4. Recipients and processors
We do not sell your data, we do not rent it, and we do not share it with data brokers. We rely on a limited set of
companies, some of which act on our instructions, and some of which act on their own account.
Processors, acting on our instructions
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Amazon Web Services (AWS): database storage and server logs, in the eu-west-3 region (Paris, European Union).
- OVH: hosting of our application server, France (European Union).
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RevenueCat: in-app purchase and entitlement management. Its software runs inside the app and is contacted at
every launch, so it receives your installation identifier, your purchase and entitlement history, the receipt
issued by the store, and the technical device and store data that it collects itself. RevenueCat, Inc. is based
in the United States.
Independent controllers, acting under their own privacy policies
We have no control over what these companies do with the data they receive, and requests concerning that data must
be addressed to them:
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Apple Inc.: purchase through the App Store, delivery of notifications through the Apple Push Notification
service, and, on iOS, the operating system backup described in section 2.9.
-
Google LLC: purchase through Google Play, delivery of notifications through Firebase Cloud Messaging, and, on
Android, the operating system backup described in section 2.9.
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Nintendo: artwork, screenshots and eShop pages loaded directly by your device, which give Nintendo's servers
your IP address (see section 5).
We use no advertising network, no analytics provider, no attribution provider and no third-party crash-reporting
provider. Public authorities may receive data where we are legally required to disclose it.
5. Hosting and international transfers
The data we store about you is held in the European Union: our database and our server logs are hosted on AWS in the
eu-west-3 region (Paris, France), and our application server runs on a machine rented from OVH, in France. Transfers
outside the European Union occur with RevenueCat, and with Apple and Google for purchases and push delivery, all of
which are established in or operate from the United States:
-
Transfers to RevenueCat, Inc. are governed by its data processing addendum, which incorporates the European
Commission's Standard Contractual Clauses.
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Transfers to Apple Inc. and Google LLC, in connection with the purchase and with the delivery of notifications,
rely on their certification under the EU-US Data Privacy Framework and, in addition, on the Standard Contractual
Clauses contained in their data processing terms.
A copy of the safeguards applicable to any of these transfers can be obtained free of charge by writing to
contact@cardslot.app. In addition, when your device loads artwork or screenshots, or when you open an eShop page, it
connects directly to Nintendo's servers; that connection is between your device and Nintendo, and is governed by the
privacy policy of Nintendo of Europe SE, available at
https://www.nintendo.com/eu/privacy-policy/.
6. Data security
All communication between the app and our server uses HTTPS. Data stored in our database and in our log storage is
encrypted at rest by our hosting provider. Access to the production environment is restricted to the developer of
the app. The app has no account and no password, so we hold no login credentials belonging to you. No method of
transmission or storage is completely secure, and we cannot guarantee absolute security; in the event of a personal
data breach likely to result in a risk to your rights and freedoms, we will notify the competent supervisory
authority and, where required, the affected users, in accordance with Articles 33 and 34 of the GDPR.
7. Data retention
The data stored on our server under your installation identifier (the unlock flag, the push registration data, your
watchlist, and your alert preferences once the app starts sending them) is kept indefinitely: it carries no expiry
date, and it is deleted only when you ask us to delete it, as explained in section 8. Uninstalling the app deletes
the data held on your device, but it does not delete the data held on our server: because the app has no account, we
have no way of knowing that an installation is gone, and reinstalling the app generates a new identifier rather than
reusing the old one, so those records simply remain in our database, unreachable, until they are deleted on request.
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Server logs, including the records described in sections 2.7 and 2.8, are automatically deleted 30 days after
they are written. They are stored as a chronological stream and cannot be searched or deleted per installation,
so a deletion request removes the records held in our database, and the corresponding log lines disappear when
those 30 days elapse.
- The connection logs of our reverse proxy, described in section 2.10, are deleted after 14 days.
Please note that our database is protected by a continuous backup mechanism (point-in-time recovery) with a 35-day
window, which means that deleted records may persist in that backup for up to 35 days before being definitively
overwritten.
8. Your rights and how to exercise them
Under Articles 15 to 21 of the GDPR you have the following rights over your personal data:
- Right of access (Art. 15): you can ask what data we hold about your installation and obtain a copy of it.
- Right to rectification (Art. 16): you can ask us to correct inaccurate or incomplete data.
- Right to erasure (Art. 17): you can ask us to delete the data we hold about your installation.
- Right to restriction of processing (Art. 18): you can ask us to limit the processing in certain cases.
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Right to data portability (Art. 20): you can ask for a copy of the data you provided in a structured,
machine-readable format.
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Right to object (Art. 21): you can object to processing based on our legitimate interest, on grounds relating to
your particular situation.
To exercise any of these rights, write to us at contact@cardslot.app and we will handle the request manually, free
of charge, within one month. Because we hold no name and no email address, the only way for us to find your data is
your installation identifier. It is displayed in the app, in Settings, just below the contact row: tap it to copy it
and paste it into your message. Without it we may be unable to identify any data relating to you, in which case, in
accordance with Article 11(2) of the GDPR, we may have to tell you that we cannot act on the request.
You can withdraw your consent to push notifications at any time by disabling notifications for the app in your
device settings; no further notification will then be sent to you. Withdrawing your consent does not affect the
lawfulness of the processing carried out before the withdrawal. The push registration data described in section 2.4
is not removed from our server automatically when you do so: write to us at contact@cardslot.app and we will delete
it, free of charge, within one month.
You have the right to lodge a complaint with your local data protection authority; in France, this is the CNIL (www.cnil.fr).
9. No advertising and no tracking
Cardslot displays no advertising. It contains no advertising SDK, no analytics SDK, no attribution or tracking SDK,
and it does not use the advertising identifier of your device. We do not track you across other apps or websites,
and we do not build advertising or behavioural profiles. The technical data described in section 2.7 is used to
operate and protect the service, not to profile you or to measure your behaviour for commercial purposes.
10. Children
Cardslot is a general-audience app and is not directed at children. Our Terms of Service reserve its use to people
aged 15 or over, or the age of digital consent in your country of residence if that age is higher. We do not
knowingly collect data from children below that age, and the app does not ask for or infer the age of its users. If
you believe that a child has provided personal data through the app, please contact us and we will delete the
corresponding data.
11. Independence and source of the price data
Cardslot is an independent application. It is not affiliated with, sponsored by, endorsed by or otherwise associated
with Nintendo, and no partnership or commercial relationship between us and Nintendo is claimed or implied.
"Nintendo", "Nintendo Switch", "Nintendo eShop" and the names, artwork and trademarks of the games listed in the app
are the property of their respective owners, and are used in the app for the sole purpose of identifying the
products they designate. Catalogue and price information shown in the app is collected from publicly accessible
Nintendo eShop sources for the European region; game artwork and screenshots are displayed from their original
locations and are not re-hosted by us. This information is provided for information purposes only, may be
incomplete, may be delayed and may be inaccurate; the price actually charged is the one displayed on the eShop at
the moment of purchase. Cardslot does not sell games and does not process any game purchase. It uses no Nintendo
account and never asks you to sign in to Nintendo: our server reads only pages and data sources that Nintendo makes
publicly accessible for its European eShop.
12. Push notifications
Push notifications are optional. They are only sent if you granted the notification permission of your operating
system, and the app will keep working without them. To deliver them, we store the push token of your device as
described in section 2.4, and we use Apple's and Google's notification services, which necessarily receive the
content of the notifications sent to you. Notification content is limited to what the feature needs: the game
concerned and the price change. Every notification we send is about a game you chose to follow — we do not send
promotional messages, and there is no notification that advertises the shop at large. No notification is sent yet:
the app already registers the push token of your device so that alerts can start without requiring a further update,
but the sending of notifications is not enabled in the current version of the service. This page will be updated,
with a new date, when it is.
13. Changes to this Privacy Policy
We may modify this Privacy Policy from time to time, in particular when a new feature changes what data is
processed. Any change will be published on this page with an updated date at the top. Where the change is
significant, we will make it visible in the app. We encourage you to review this page from time to time.
14. Contact
If you have any question about this Privacy Policy, about how your data is processed, or if you wish to exercise any
of the rights described in section 8, please write to us at contact@cardslot.app.