Privacy Policy

Last updated: 5 November 2026 · Policy version 2026-11-04

This policy explains how Calcly (the "app") and its website (https://icalc-app-33a0e.web.app) handle your information. The app is published by Diego Ferreira, based in Ireland, under the name DF Dev Apps. Diego Ferreira is the data controller under the EU General Data Protection Regulation (GDPR) ("we", "us"). You can reach us at df.dev.ie@gmail.com.

This version describes Calcly 2.1 and later. If you still use Calcly 2.0, see If you use Calcly 2.0 below.

The short version

• Your calculations, your history and your settings stay on your device.
• The app uses Google Firebase for usage statistics, crash reports and performance measurements. This data is linked to random IDs for your installation of the app, not to your name or email address.
• The first time you open the app, a privacy screen explains this. Until you answer it, the app sends no usage statistics, crash reports or performance measurements. In the European Economic Area (EEA), the UK and Switzerland, and wherever the app can't tell your region, it then sends them only if you agree. Elsewhere, they are on by default, and you can turn each one off on that screen or later.
• You can change your choices at any time in Settings > Privacy. Delete my data, also there, deletes the IDs that link this data to your installation.
• The app shows ads from Google AdMob. In the EEA, the UK and Switzerland, Google's consent message asks you first, and ads are personalized only if you agree.
• The app has no accounts and no in-app purchases.
• We don't sell your personal data.

Information stored on your device

• Your history: your most recent calculations (up to 1,000), stored in the app's private storage. You can delete one, or all of them with Clear, on the History screen.
• Your settings: the theme, haptic feedback, the last calculator mode and the units you chose in the converter.
• What the app needs to work: how many calculations you have done, to decide when to show Google Play's rating prompt, and when an ad was last shown, to limit how often ads appear.
• Your privacy choices: what you chose for each purpose, when, which version of this policy you saw and the region the app detected, plus a log of your last 50 changes, so the app can apply your choices and show what you chose. The region comes from Google's consent check (below) and from your mobile network's and SIM card's country; if the app can't tell, it treats you as being in the EEA.
• Your choices for ads: Google's consent message stores your choices for ads on your device (see Advertising).
• Backups: the app turns off Android's backup, so none of this is included in your device backups.

This information isn't sent to us. Deleting the app, or clearing its data, deletes all of it.

Information we collect

The app uses the Google Firebase services described below. Google processes this data for us, as our processor, under the Firebase Data Processing and Security Terms. Firebase identifies your installation of the app only by random IDs: a Firebase installation ID and, for Analytics, an app instance ID. The installation ID is kept until you use Delete my data, and Firebase then deletes it within 180 days. More information: Privacy and Security in Firebase and the Google Privacy Policy.

Ads work differently: Google and its ad partners decide for themselves how they use the data they receive for ads (see Advertising).

Legal basis. In the EEA, the UK and Switzerland, and wherever the app can't tell your region, usage statistics, crash reports and performance measurements are collected only with your consent (GDPR Article 6(1)(a)). You give or refuse it on the privacy screen the app shows the first time you open it, and you can change it later in Settings > Privacy. Elsewhere, they are on by default, based on our legitimate interest in keeping the app working and improving it (Article 6(1)(f)). The same screen tells you about them before anything is sent, and you can object at any time by turning them off, on that screen or in Settings > Privacy.

Usage statistics (Google Analytics for Firebase)

• What: the screens and features you use (for example, which calculator mode or converter category), with the app version, device model, operating system version, language, time zone, how the app was installed (for example from Google Play), your approximate location (country, region or city, derived from your IP address, which Analytics doesn't store) and the app instance ID. The numbers you type and your results are never sent.
• Advertising ID: Analytics may also receive your device's advertising ID to measure ads. In the EEA, the UK and Switzerland, it does so only if you agree in Google's consent message.
• Ads measurement: Analytics is linked to AdMob to measure ads. Analytics therefore also records the ads you see and tap in the app, and Google uses this data in AdMob, as an independent controller (see Advertising). Google signals, which would combine this data with Google accounts, is turned off.
• Purpose: to understand which features are used, so we know what to improve.
• Legal basis: consent in the EEA, the UK and Switzerland; legitimate interest elsewhere (see above).
• Retention: event data linked to the app instance ID is kept for 2 months, the period we set in Google Analytics. After that, only aggregated statistics remain (Google Analytics data retention).
• Turn it off: Settings > Privacy > Usage statistics.
• How Google uses it: How Google uses information from sites or apps that use our services.

Crash reports (Firebase Crashlytics)

• What: when the app crashes or an operation fails, a technical report. It contains what the app was doing (the stack trace), the app version, device model, operating system version, free memory and storage, and random installation IDs. The app records a report only while crash reports are allowed. We don't add your calculations to these reports.
• Purpose: to find and fix bugs.
• Legal basis: consent in the EEA, the UK and Switzerland; legitimate interest elsewhere.
• Retention: 90 days.
• Turn it off: Settings > Privacy > Crash reports. Reports not yet sent are deleted.

Performance measurements (Firebase Performance Monitoring)

• What: how long things take, such as starting the app, drawing screens and network requests. Each measurement comes with the app version, device model, operating system version, network type, mobile carrier, country (derived from your IP address) and a random installation ID. While measurements are on, Performance Monitoring downloads its own settings from Firebase Remote Config, using the installation ID.
• Purpose: to find and fix slow parts of the app.
• Legal basis: consent in the EEA, the UK and Switzerland; legitimate interest elsewhere.
• Retention: events linked to an IP address are kept for 30 days, and other performance data for 60 days.
• Turn it off: Settings > Privacy > Performance data.

App updates (Google Play)

• What: when it starts, the app asks Google Play whether a newer version exists. If one does, Google Play shows its update screen and installs the update for you.
• Purpose: to keep the app working and secure.
• Legal basis: our legitimate interest in operating the app and keeping it secure (Article 6(1)(f)). Google Play handles this under its own terms, and we don't receive any data from it.

Feedback you send from the app

• What: the message you type in Send us Feedback, with the app's package name (com.icalc), platform (Android) and version. The app adds no name, email address or ID. If you'd like a reply, include your email address in the message.
• Where: the message is sent over an encrypted connection to our feedback service on Google Cloud, which stores it in our database. Like any web server, the service logs the IP address each message came from. Google keeps these logs for 30 days.
• Purpose and legal basis: to read your feedback and improve the app, which is our legitimate interest (Article 6(1)(f)).
• Retention: up to 24 months, then deleted.

Advertising

The app is free and shows ads from Google AdMob. An ad may appear when you come back to the app, at most once every 4 hours, and never the first time you open it. Ads never appear while you are using the app. The app requests ads only after you have answered its privacy screen and, where it is shown, Google's consent message.

Ads (Google AdMob)

• What: the Google Mobile Ads SDK in the app sends Google AdMob your IP address (from which Google derives your approximate location), information about your device and the app (such as the device model, operating system, network type, language and app version), the ads you see and tap, and diagnostic information.
• Device identifiers: your device's advertising ID and the app set ID. In the EEA, the UK and Switzerland, Google uses them only as far as you allow in Google's consent message. On Android versions that offer it, the ads SDK may also use Android's Privacy Sandbox attribution reporting, which you control in your device's privacy settings.
• Purpose: to show ads, measure how they perform, limit how often you see the same ad, and prevent fraud and abuse. Ads are personalized only where your choices allow it.
• Who decides: Google and the ad partners listed in Google's consent message use this data as independent controllers, under their own policies, not as our processors. See the Google Ads Controller-Controller Data Protection Terms, How Google uses information from sites or apps that use our services and Advertising at Google.
• Legal basis: in the EEA, the UK and Switzerland, your consent (Article 6(1)(a)), which you give or refuse in Google's consent message the first time you open the app. If you refuse, you still see ads, but they aren't personalized, and Google uses only the data your choices allow. Elsewhere, our legitimate interest in funding the app with ads (Article 6(1)(f)).
• Retention: Google and each partner decide how long they keep this data, under their own policies (how Google retains data).
• Your choices: Settings > Privacy > Ad privacy choices, shown where the law requires a consent message, reopens Google's consent message, so you can change or withdraw your consent at any time. You can also reset or delete your advertising ID in your device's settings.

Google's consent message (Google User Messaging Platform)

Google's consent message comes from the Google User Messaging Platform (UMP), Google's consent management platform for ads, which works with the IAB Europe Transparency and Consent Framework (TCF). Google's EU user consent policy requires us to ask for this consent.

• What: each time the app starts, UMP asks Google whether a consent message is needed where you are. The request carries your IP address (from which Google works out your region), information about your device and the app, and your current choices. UMP stores your choices on your device in the TCF format, and the ads SDK sends them with each ad request, so Google and its ad partners know what you allowed.
• Purpose: to ask for your consent where the law requires it, and to apply and record your choices.
• Legal basis: our legal obligation to ask for your consent where the law requires it, and to be able to show what you chose (GDPR Articles 6(1)(c) and 7(1)). Storing your choices on your device is strictly necessary for this.
• Retention: your choices stay on your device until you change them or delete the app. Google's message may ask you again, for example when the list of ad partners changes. Google keeps the request data under its own retention policy.
• Change your choices: Settings > Privacy > Ad privacy choices (see above).

Your choices and Delete my data

• Settings > Privacy has a switch for each of usage statistics, crash reports and performance data. A change applies at once, and when you turn crash reports off, reports not yet sent are deleted.
• Ad privacy choices, also in Settings > Privacy where the law requires a consent message, reopens Google's consent message for ads.
• Delete my data asks you to confirm, then turns every switch off, resets the Analytics data and its ID, deletes crash reports not yet sent and deletes the app's Firebase installation ID. Your history stays on your device.
• It then opens an email to us with your installation's Analytics ID, for you to send, so we can ask Google to delete the usage statistics it already has. Google removes that data from reports within 72 hours and deletes it within about 2 months. Statistics already aggregated aren't affected.
• Crash reports and performance data can't be deleted for a single installation. They expire after the periods above.
• Delete my data doesn't reach the data Google and its ad partners received for ads, which they control. For that, use Ad privacy choices and your device's advertising ID settings (see Advertising).
• Being asked again: when the version of this policy changes, the app shows its privacy screen again and sends no usage statistics, crash reports or performance measurements until you answer. If you decline something, it doesn't ask you again for at least 6 months, unless the policy version changes.

Information we do not collect

The app doesn't collect your name, email address, phone number, contacts, precise location, photos, microphone or camera, and it has no accounts. Your calculations never leave your device, unless you copy them yourself or put them in feedback.

The app asks for no permission at runtime. It uses permissions Android grants when the app is installed: internet access and network state (for the services above), vibration (for haptic feedback, if you turn it on), and those the ads and Firebase SDKs need, such as access to the advertising ID, basic phone state (the network type, for the ads SDK), Android's Privacy Sandbox attribution reporting and Google Play's install referrer.

When you contact us

If you email us, we receive what you choose to send: usually your name, email address and message. Contact links open your own email app, so your message reaches us as an ordinary email.

• Purpose: to answer your message, to fix problems you report and to handle requests about your data, such as those from Delete my data.
• Legal basis: our legitimate interest in responding to inquiries and improving the app (GDPR Article 6(1)(f)), and, for requests about your rights, our legal obligation to handle them (Article 6(1)(c)).
• Retention: up to 24 months after our last contact with you, then deleted.
• Email provider: our mailbox is Gmail, provided by Google under the Google Privacy Policy. Messages may be stored outside the EEA.

We never sell your information or use it for marketing.

Where your data is processed

Google may process the data described in this policy outside the EEA, including in the United States. Transfers to Google LLC rely on the EU-US Data Privacy Framework, its UK Extension and the Swiss-US Data Privacy Framework, under which Google LLC is certified. Other transfers rely on the European Commission's Standard Contractual Clauses, which are part of Google's data processing terms.

For ads, Google and the ad partners listed in Google's consent message may also process data outside the EEA, including in the United States, under the safeguards in their own terms, such as the Google Ads Controller-Controller Data Protection Terms.

Our feedback service processes the feedback you send from the app in Google Cloud's São Paulo region (Brazil), under the same safeguards.

Security

Everything the app sends travels over encrypted connections (TLS). Google stores the Firebase data encrypted at rest, and in Firebase only our developer account can access it. Third parties that receive data through the app, such as Google, are bound by their terms to protect it at least as well as this policy describes. Your history, settings and privacy choices stay in the app's private storage on your device.

Our website

The website is a static site on Firebase Hosting. When you visit it, Google processes your IP address and basic request details (such as the page requested and your browser type) to deliver the site and protect it from abuse. This is based on our legitimate interest in running a secure website (Article 6(1)(f)). Google keeps the IP data for a few months. The website uses no cookies, scripts, analytics, tracking or ads.

Ratings and store statistics

After you've used the app for a while, it may show Google Play's own rating prompt (Google Play In-App Review). Your rating and review go to Google Play under its terms, and we only see what Google Play publishes. Depending on your device settings, Google Play may also share crash statistics and aggregated data, such as download counts, with developers. This data doesn't identify you to us.

Children

The app is meant for a general audience and isn't directed at children. We don't knowingly collect personal data from children. If you are under 16, or under the age of digital consent where you live, ask a parent or guardian before you allow optional data collection or personalized ads. If you think a child has sent us personal data, for example in feedback, contact us and we'll delete it.

Your rights

Under the GDPR, you can ask us for access to your personal data, and ask us to correct or delete it, to restrict or object to its processing, or to give it to you in a portable format. Where we rely on your consent, you can withdraw it at any time in Settings > Privacy, or for ads in Ad privacy choices, as easily as you gave it. Withdrawing doesn't affect processing that happened before. Where we rely on our legitimate interest, you can object at any time, in Settings > Privacy or by email. To exercise your rights, email df.dev.ie@gmail.com. We reply within one month.

For ads data, which Google and its ad partners control, use the choices under Advertising, or contact them through their own privacy policies.

You don't have to provide any of this data: the app works the same with every switch in Settings > Privacy turned off. The app doesn't make decisions about you based solely on automated processing that have legal or similarly significant effects on you.

You can also complain to the Data Protection Commission in Ireland (www.dataprotection.ie), or to the data protection authority where you live or work, such as the ICO in the UK.

If you use Calcly 2.0

Calcly 2.0, the version before 2.1, has no privacy screen and no switches for usage statistics, crash reports and performance measurements. It sends them once Google's consent message for ads has been answered, where it is shown, and right away elsewhere, whatever you choose in that message, based on our legitimate interest (Article 6(1)(f)), and it sends crash reports as soon as they are recorded. Its choices for ads are under Settings > Privacy options. To object, update the app to the latest version, which asks you first, or email us. Uninstalling the app stops all collection.

Changes to this policy

We may update this policy. The date at the top shows when it last changed. The policy version changes when what the app collects, why, who processes it or how long it's kept changes, and Settings > Privacy shows the version your current choices refer to. The app then shows its privacy screen again (see Your choices and Delete my data). We note significant changes in the app's release notes. If a translation of this policy differs from this English version, the English version applies.

Contact

• Diego Ferreira (DF Dev Apps), Ireland
• Email: df.dev.ie@gmail.com
• Website: https://icalc-app-33a0e.web.app
• Developer website: https://appcraftlabs.com