What this policy covers
This policy explains how the Scale Calculator app for Android (package com.calculatescale.app) handles your information. The app is developed and published by Tomasz Warezak, who also runs CalculateScale.com, and you can find it on Google Play.
It describes the app only. The website you are reading this on is a separate matter: it uses cookies and analytics, and those are covered by the website privacy and cookie policy.
The short version
- There is no account, no sign-up and no login.
- The scales, lengths and units you type stay on your phone and are never sent anywhere.
- The calculator screen shows one advertising banner from Google AdMob.
- Since version 1.6 the app also counts which of its features are used, through Google Analytics for Firebase. In the European Economic Area, the United Kingdom and Switzerland it does so only if you agree.
- We run no server of our own. What we see are statistics compiled by Google, never your numbers.
What reaches us
The app talks to no server of ours, so nothing from it reaches us directly, and we never see the scales and measurements you work with.
What we do see are reports compiled by Google: the usage statistics described in the next section, and the figures Google Play and AdMob provide, such as how many people installed the app, how it is rated, how often it crashed, how many ads were shown and what they earned. None of these reports names a person.
Usage statistics
To decide what to improve, the app reports which of its features are used. It does this through Google Analytics for Firebase, a Google service that processes the data on our behalf.
The app itself sends these events:
- a scale was picked from the list, with the scale and the section it is listed under, for example 1:87 under models;
- the padlock was opened to calculate the scale from two lengths;
- a unit from the other measuring system was chosen, with only the system: metric or imperial;
- the calculator was switched to area or volume;
- the panel that fits a drawing to a sheet was opened, and a scale was set from it, with only the paper size.
Google Analytics adds a few events of its own, such as the first time the app is opened, the start of a session, how long the app was in use and an app update. With every event it records technical details of the device and the app: the model, the Android version, the language, the app version, where the app was installed from, and the country and region derived from the IP address. Google does not store the IP address itself for this.
The events are tied to an app-instance identifier, a random number that Firebase creates on your phone. It is not your advertising ID: the app does not give Analytics the advertising ID or the Android device ID, and nothing in the statistics carries your name or contact details. Clearing the app's storage or uninstalling the app replaces the identifier with a new one.
No number you type is ever part of an event. Not the lengths, not a scale you type by hand, not the size of an object you fit to a sheet.
We see the results as reports: how many people use a feature, how often and in which countries. Google keeps the event-level data for two months, after which only the aggregated reports remain.
Advertising
The calculator screen carries a single banner at the bottom, served by Google AdMob through the Google Mobile Ads SDK. Together with the usage statistics, it is the only reason the app connects to the internet.
To fill that banner, Google receives data from your device and processes it under its own responsibility:
- the advertising ID of the device, a resettable identifier that Android provides for this purpose;
- the IP address, from which Google derives an approximate location, usually down to the city;
- technical details of the device and the app, such as the model, the Android version, the language and the app version;
- what happened to the banner: that it was requested, shown, or tapped.
Google uses this to select and measure ads, to cap how often you see the same one and to catch fraudulent clicks. Depending on the choice described in the next section, it may also use it for personalised advertising. The details are in How Google uses information from sites or apps that use our services and in the Google Privacy Policy.
We have no access to any of it. Our AdMob account shows how many ads were shown and what they earned, nothing about who saw them.
Nothing you type takes part in this. Your numbers are not sent with the ad request and are not used to target ads.
Your choices
If you are in the European Economic Area, the United Kingdom or Switzerland, the app shows Google's consent form the first time you open it. The form asks whether Google may use your data for personalised ads and whether the app may measure how it is used. You can say no to either.
- If you refuse personalised ads, the banner still appears, but it is filled with a non-personalised ad, chosen from the context of the moment instead of from a profile.
- If you refuse measurement, the usage statistics are off. The app sends none until you agree, and none while the form has not been answered yet.
Wherever that form applies, the app also keeps a Privacy options entry in the menu in the top right corner. Open it whenever you want to see your answer again or change it. A change takes effect straight away, without restarting the app.
Outside those regions the app does not show the form, and the usage statistics are on. They contain nothing you type and nothing linked to your name. Clearing the app's storage resets the identifier they are tied to, and uninstalling the app stops them.
Separately from the app, Android lets you reset or delete the advertising ID in your device settings, under privacy and then ads (the exact path differs between phones). Deleting it stops apps, this one included, from receiving an identifier at all.
What stays on your device
This is what the app keeps on your phone:
- Where you left the calculator, and the settings you choose. The app remembers the scale, the lengths and units you typed, the size and paper you last used to fit a drawing to a sheet, and choices such as the interface language or whether the welcome screen should appear again, so that it opens as you left it. All of this sits in the app's private storage, where other apps cannot read it, and none of it leaves the device.
- Your answer to the consent form, stored on the device by Google's consent library so that you are not asked again at every launch.
- The app-instance identifier used by the usage statistics, and any statistics waiting to be sent while the phone is offline.
Android may include this app data in the device backup that the system makes to your own Google account, together with the data of your other apps. That backup belongs to you and is handled by Google under its own terms. We have no access to it, and you can switch device backup off in your Android settings.
Uninstalling the app removes its data from the device.
Permissions the app requests
Android installs the app without asking you to approve anything, because none of these permissions reaches your personal content. They come with the advertising and the usage statistics:
INTERNETandACCESS_NETWORK_STATE— to request the banner, to send the usage statistics and to notice when the device is offline. The calculator itself needs no connection; in airplane mode you simply get no banner, and the statistics are sent later.com.google.android.gms.permission.AD_ID— to read the advertising ID for the banner, as described above. The usage statistics do not use it.com.google.android.finsky.permission.BIND_GET_INSTALL_REFERRER_SERVICE— added by Google Analytics to ask Google Play where the install came from, for example the store listing or a search.ACCESS_ADSERVICES_TOPICS,ACCESS_ADSERVICES_ATTRIBUTION,ACCESS_ADSERVICES_AD_ID,WAKE_LOCKandFOREGROUND_SERVICE— added by Google's libraries so that an ad request, its measurement and the sending of statistics can finish even if you leave the app.com.calculatescale.app.DYNAMIC_RECEIVER_NOT_EXPORTED_PERMISSION— declared by Android's own support library and usable only inside this app.
The app asks for no access to your contacts, precise location, camera, microphone, photos or files.
Who receives your data
Google, in three roles: as the provider of the advertising inside the app, as the provider of the usage statistics, which it processes on our behalf, and as the operator of the store the app is distributed through. No one else. There is no other third-party service in the app, no data broker and no server of ours.
Children
The app is a general-purpose calculation tool. It is not directed at children and is not part of any Google Play programme for families. If you are setting up a phone for a child, note that the app shows advertising served by Google and, outside the regions where it asks first, sends usage statistics to Google.
Your rights and how to reach us
Data protection law gives you the right to see, correct or delete the personal data a company holds about you. The only data about your use of the app that we can see are the usage statistics. They are not linked to a name, an email address or an advertising ID, so we have no way to find the ones that come from your phone. Clearing the app's storage cuts the link between your phone and the statistics already sent, and refusing measurement in Privacy options stops new ones.
For the data Google processes for advertising, the routes are Google's: the consent form in the app, the advertising ID controls in your Android settings, and the contact details in the Google Privacy Policy.
If you have a question about this policy or about the app, write to [email protected].
Changes to this policy
If a future version of the app does something that affects your privacy, we will update this page and change the date below before that version is released. This text replaces the version dated 26 August 2026, which described the app before version 1.6 added usage statistics.