Fair Calculator — Privacy Policy

Last updated October 1, 2026

This Privacy Policy explains how Fair Calculator (“the app”), provided by Cheng Kam To, collects, uses, and protects your information. By using the app you agree to this policy. Where we rely on your consent — for tracking, and where the law requires it, for advertising — the app asks for it separately, and you can withdraw it as described below.

Information We Collect

We collect none of your content. The app has no account and no sign-in, and we run no server for it. Nothing you enter — no amount, no name, no other detail and no result — is ever sent to us, and we have no means of seeing it.

What you enter is used on your iPhone to calculate the split, and is discarded when you leave the calculator screen. The app itself saves one thing on your device: the language you chose in its Settings.

The free version shows advertising, supplied by Google AdMob. Google’s advertising and consent libraries connect to Google to check whether a consent message is needed and to fetch ads, and they collect information of their own when they do. That is set out under Advertising and Tracking below. Nothing you enter is given to them.

We collect statistics about how the app is used, through Google Firebase Analytics: which screens you open, which calculator gave you an answer or was cleared, a change of language, and whether Premium was bought or restored; Firebase also records App Store purchases and subscription events itself, with the product and its price. They never contain an amount you entered, a name or anything else you typed, and they are tied to no name and no account, because the app has neither — but they are linked to a random identifier for your installation of the app. This applies to the free version and to Premium alike. What they contain is described under Usage Analytics below.

The app has no crash reporting of its own. Apart from Google’s libraries, the only connections the app makes are to Apple, to check and process the Premium subscription. Links in Settings and on the Premium screen open this website and Apple’s terms in Safari, and carry nothing about you beyond the language of the page; Manage Subscription opens your App Store account.

The app requests one permission only. It does not use the camera, the microphone, your photos, your contacts, your location or notifications. The only permission it requests is Apple’s tracking permission, described below, and it does not request it while a Premium subscription is active.

How We Use Your Information

What you enter is used for one purpose: to calculate who should pay how much, and to show you that result with a short explanation of how it was calculated. The calculation runs entirely on your device. What you enter is never uploaded, never sold and never shared, unless you share a result yourself.

Your language setting is used to show the app in the language you chose.

The usage statistics are used for one thing: to decide what to improve — for example, which calculators people actually use. They are not used for advertising, not sold, and not shared with anyone beyond Google as our analytics provider.

Google’s advertising and consent libraries use the information they collect, described under Advertising and Tracking, for the purposes the app’s App Store privacy label lists: to serve, limit and measure the ads shown in the app, which earn revenue for us (Third-Party Advertising and Developer’s Advertising); to report how those ads perform (Analytics); and, for the consent library, to work out whether a consent message is needed where you are and to show it (App Functionality). We receive only the aggregated reports described there.

We do not build a profile of you, we do not combine anything you enter with any other information, and nothing you enter is used for advertising.

Your Calculations

Fair Calculator works with what you type into it — amounts of money, the names of the people sharing a cost, and details such as distances, nights stayed or a discount — and nothing else.

What is collected. Nothing is collected by us. While a calculator screen is open, the values you enter are held in the app’s memory, so that the result can be calculated and shown to you. The app does not save them, keeps no history of past calculations, and restores nothing you entered the next time it starts.

What it is used for. Only to produce the result on your screen. It is never used for advertising, profiling, analytics or any other purpose, and it is never passed to Google’s advertising or analytics libraries.

Where it is stored. Only in the app’s memory, while the calculator screen is open. The app never writes it to a file, to iCloud, to your iPhone backup or to any server of ours. Like every app, iOS may keep a picture of the last screen you saw for the app switcher; that picture stays on your iPhone.

Who it is disclosed or shared with: nobody, unless you share it yourself. It is never sent to us, to an advertising network, to an analytics service or to any other third party. The one way a result can leave your device is the Share result button, described in the next section, which only you can use.

How long it is kept, and how to delete it. Until you leave the calculator screen, tap Clear, or the app is quit — swiped away in the app switcher, or ended by iOS. If you only switch to another app, the screen is still there when you come back. Because the app saves nothing, there is nothing for you to delete afterwards, and no copy of it for us to hold.

Sharing a Result

Once a result is calculated, the calculator shows a Share result button below it. When you tap it, the app opens the iOS share sheet with a short text summary: which calculator it is, each person’s name and amount — with a short detail such as nights stayed, where one applies — the total, and the explanation shown with the result.

The app never sends this summary itself. Where it goes — a message, a note, an email — is your choice in the share sheet, and from then on it is handled by the app you chose and governed by that app’s own privacy policy. Nothing is shared unless you tap the button.

Usage Analytics

Fair Calculator uses Google Firebase Analytics to count how the app is used. It is on in the free version and with Premium, and it does not depend on the tracking permission, because it does not use your device’s advertising identifier.

What the app chooses to send. A short, fixed set of events: a calculator gave its first answer since you opened it, you tapped through to the answer and its explanation, you tapped Clear, you changed the app’s language, and Premium was bought, or Restore Purchases was tapped and found or did not find it. Each carries at most one detail from a fixed list built into the app — which of the ten calculators, which language, or yes or no. Alongside them the app records which of its screens you are on (home, a calculator, Settings, the language list, the Premium screen), also from a fixed list.

What the app cannot send. No amount, no name, no distance, no result and nothing else you typed. The app’s own source code allows an event to carry only one of its own fixed words, so what you enter cannot reach the analytics system at all. The app sets no user ID, and the app’s own purchase event carries no price and nothing about your Apple Account.

What Firebase collects that we do not choose. Any app using Firebase Analytics also sends, automatically:

• an app-instance identifier — a random value created when you install the app, tied to no account, and shared with no other app;
• automatic events such as first open, session start, app update and OS update;
• App Store purchase and subscription events — a purchase, renewal, conversion from a trial or cancellation of Premium — with the product, its price and currency, and never your Apple Account;
• your device model, iOS version, app version and language;
• an approximate location, worked out from your IP address, at roughly city-or-region level.

The version of Firebase in the app has no support for the advertising identifier, and the app’s configuration switches off Google’s advertising signals, Firebase’s registration with Apple’s SKAdNetwork, and the collection of your device’s vendor identifier. Every event, including the purchase events, is sent linked to the app-instance identifier, so Google can tell that events came from the same installation, and the app’s App Store privacy label declares this data as linked accordingly. We do not receive your name, your email address, your phone number or your precise location, and we have no way to connect an app instance to a person.

Google’s own description of how it handles data from apps that use its services is at policies.google.com/technologies/partner-sites, and Firebase’s privacy documentation is at firebase.google.com/support/privacy.

Advertising and Tracking

The free version of Fair Calculator shows ads supplied by Google AdMob. The app uses banner ads only: a single banner at the bottom of the home screen and the calculator screens, hidden while the keyboard is open. It shows no full-screen (interstitial) or rewarded ads. Ads are limited to content suitable for a general audience; you can report an unsuitable one through the feedback form.

We add nothing about you to ad requests. An ad request from this app carries no keywords, no interests, no custom targeting and nothing you have entered.

What Google collects. Checking consent and requesting an ad are connections to Google, and Google’s libraries send their own information with them: your device model and operating system, technical details about the device such as battery level, volume and available storage, your IP address — from which Google derives an approximate location, at roughly city-or-region level — which app is asking, the ads you are shown and how you interact with them and with the app, device identifiers that Google uses for purposes such as fraud prevention and frequency capping, and, only if you allow tracking, your device’s advertising identifier. They also collect operational diagnostics about their own code, including crashes and performance. Google may link this information to your device, and the app’s App Store privacy label declares it accordingly. It is governed by Google’s privacy policy and Google’s advertising policies; how Google uses information from apps that use its services is described at policies.google.com/technologies/partner-sites.

What we receive. Only aggregated AdMob reports — for example, how many ads were shown and what they earned, by country — which we use to understand how advertising in the app performs. Nothing in them identifies you or your device.

Consent where the law requires it. If you are in a region where consent is required for advertising — such as the European Economic Area or the United Kingdom — Google’s consent message is shown on first launch, before any ad is requested. If you do not consent, Google may still show limited or non-personalised ads, as its consent framework allows, without using your information to personalise them. You can change your answer at any time in the app, under Settings > Ad Privacy Options. If you withdraw consent there, Google likewise shows only limited or non-personalised ads, as its consent framework allows.

The app asks for tracking permission. Normally after Google’s consent message, where one is shown, the app shows Apple’s App Tracking Transparency prompt, once per install. The question is whether Google may use this device’s advertising identifier to show you more relevant ads and to measure how ads perform.

If you allow it, Google may use your device’s advertising identifier to personalise the ads you see and to measure them. Apple counts this as tracking, and the app’s App Store privacy label says so. Google’s handling of the identifier is governed by Google’s privacy policy, not by us.

If you decline, the app instructs Google’s advertising library not to personalise ads, Google is not given your device’s advertising identifier, and the ads you see are non-personalised. Google still receives the other information listed above with each ad request, in order to serve, limit and measure those ads. Every feature of the app works exactly the same either way, and nothing is withheld from you for declining.

You can change your answer at any time on your iPhone, in Settings → Privacy & Security → Tracking. If Allow Apps to Request to Track is switched off there, the app never asks, and is treated as declined. The app applies a changed answer the next time it comes to the foreground.

When an ad leads you to install another app, Apple’s SKAdNetwork may report the result to the ad network concerned, in a form that does not identify you.

A Premium subscription removes advertising entirely. From the moment you subscribe, no ad is requested and the banner is removed. From the next launch, the app does not start Google’s advertising and consent libraries at all, and neither the consent message nor the tracking prompt is shown. Usage analytics, described above, continues with Premium.

Premium Subscription

Premium is an optional yearly subscription. It renews automatically unless it is cancelled at least 24 hours before the end of the current period, and you can manage or cancel it in your App Store account settings.

Payment is handled entirely by Apple. We receive no name, no payment details and no Apple Account information. The app asks Apple’s StoreKit, on your device, whether your subscription is active; Restore Purchases in the app’s Settings asks Apple to check again.

Third-Party Services

Apple, for the App Store, the Premium subscription, the share sheet and SKAdNetwork; Google Firebase Analytics, for the usage statistics described above; and, in the free version, Google AdMob and Google’s consent message, for the advertising described above.

Apart from Apple, as the platform and payment provider, Google is the only third party that receives information through the app, and we confirm that it provides the same or equal protection of that information as stated in this policy and as required by Apple’s App Store Review Guidelines. There are no others: we use no other analytics service, and no crash reporter, cloud database or AI service. Google’s libraries collect their own diagnostics, as described above. Nothing you enter is sent to any of them. The feedback form on this website is covered by the techhkg.com privacy policy.

Data Retention

We keep none of your content, because we never receive it. What you enter is discarded as described under Your Calculations. Your language setting stays on your device — and, like any app setting, in your device backups — until you change it or delete the app.

The usage statistics are held by Google for 2 months, the retention period set on our Firebase property, and only as aggregate totals after that; Google describes how this works at support.google.com/analytics/answer/7667196. Google processes them as our processor under the Firebase Data Processing and Security Terms, which may involve storage and processing on servers outside your country.

Information that Google collects in order to serve and measure advertising is held by Google under its own retention policies, not by us. We hold only the aggregated AdMob reports described above.

Your Choices and Deletion

Tap Clear on a calculator to empty it at once, or simply leave the screen. Deleting the app removes everything it holds on your device: the language setting, the consent choice and advertising settings stored by Google’s libraries, and Firebase’s app-instance identifier — a later reinstall is a new, unconnected install.

Tracking permission for Fair Calculator can be changed at any time on your iPhone, in Settings → Privacy & Security → Tracking, and, where it applies, your advertising consent in the app, under Settings > Ad Privacy Options.

Depending on where you live, you may have rights to access, correct, delete or object to the processing of personal data about you. We hold no account and no content of yours, so there is nothing of yours for us to return or delete. For information Google collects through advertising, Google’s own tools at myadcenter.google.com and myaccount.google.com/data-and-privacy apply. For any request to us, including deletion of a message you sent through the feedback form, write to us using the contact route below and we will respond.

Children’s Privacy

Fair Calculator is a general-audience utility. It is not directed to children under 13, and we do not knowingly collect personal information from them.

The advertising the app shows is limited to content suitable for a general audience.

Changes to This Policy

We may update this policy from time to time. The date at the top of this page reflects the latest version.

Contact

Questions about this policy, or a request about your data? Send them through our feedback form.