DCZT

App Privacy Policy

DCZT built DCZT apps for the Google Play Store and App Store. This SERVICE is provided by DCZT at no cost and is intended for use as is as a commercial service.

This page is used to inform visitors regarding my policies with the collection, use, and disclosure of Personal Information if anyone decides to use my Service.

If you choose to use my Service, then you agree to the collection and use of information in relation to this policy. The Personal Information that I collect is used for providing and improving the Service. I will not use or share your information with anyone except as described in this Privacy Policy.

The terms used in this Privacy Policy have the same meanings as in our Terms and Conditions, which is accessible at my Google Play apps or App Store apps unless otherwise defined in this Privacy Policy.

Information Collection and Use

DCZT apps does not ask you to create an account, and I do not run servers that store your personal data. What you create in the app stays on your device or in your own iCloud account (see "Data stored on your device" below), apart from what you choose to send for AI processing (see "AI processing" below).

The app uses the third-party services listed below, to show advertising and to understand how the app is used. Each one receives only what it needs for the purpose shown next to it, and each has its own privacy policy, linked here, which describes exactly what it collects and how you can exercise your rights with it:

Advertising

The free version of DCZT apps is paid for by ads. Ads are provided by third-party advertising partners, which compete for each ad through Unity LevelPlay mediation. The advertising partners that may serve ads in the app are Google AdMob, Unity Ads, ironSource Ads (Unity LevelPlay), AppLovin, Meta Audience Network, Mintegral.

To show and measure ads, these partners receive information about your device: the advertising identifier of your device (Google Advertising ID on Android, IDFA on iOS - where you have allowed it), your IP address (from which they derive an approximate location such as your country or city), device model, operating system and language, and information about the ads shown and how you interacted with them. They may use this to show you ads that are more relevant to you and to measure the performance of their campaigns, including across other apps and websites.

Your choices. In the European Economic Area, the United Kingdom and Switzerland the app asks for your consent before personalized ads are shown, and you can change that choice at any time from the app's settings. If you decline, you still see ads, but they are not personalized. On iOS the app asks for permission to track through Apple's App Tracking Transparency prompt; if you decline, your advertising identifier is not shared. On any device you can reset or delete your advertising identifier, or opt out of personalized ads, in the system settings (Android: Settings > Google > Ads; iOS: Settings > Privacy & Security > Tracking, and Apple Advertising). Buying the ad-free upgrade removes the ads entirely, apart from rewarded videos you choose to watch.

Analytics

I use GameAnalytics, Firebase Analytics (Google) and Firebase Crashlytics (Google) to understand how the app is used and to find errors, so that I can improve it. This collects a device identifier, your device model, operating system and language, your country (derived from your IP address), how long you use the app and which features you use, whether you have made an in-app purchase, and error reports if something goes wrong. I do not use this information to show you ads, and I do not sell it.

Chart AI's Firebase Analytics can read your device's advertising identifier if you allow tracking in Apple's App Tracking Transparency prompt, or the Google Advertising ID on Android; it is used for analytics only. HabitKeep's Firebase Analytics is set up not to collect it.

Purchases

In-app purchases and subscriptions are processed by Apple (App Store) or Google (Google Play). I never see or store your payment details; the app only keeps a record on your device of which purchases are active, so that it can unlock what you paid for.

Data stored on your device

Everything you create or save in the apps - such as your settings, progress, wheels, habits, meals, documents and history - is stored on your device, and in your own iCloud as described below, and is not uploaded to me. If you choose to share something from the app, it is handed to the app you pick through your device's share function and leaves your device only then. Deleting the app deletes the copy on your device.

HabitKeep can sync your habits through your private iCloud database, and PDF Go can keep documents in your own iCloud Drive. That storage belongs to your Apple Account: Apple stores it, and I cannot see or access it.

Which app uses which service

The Unity apps - Antistress Games, Bits: Offline Games No WiFi, 1 2 3 4 Player Games, Spin The Wheel - Choose, Speaker Cleaner, Frequency Generator, Yes or No - Decision Maker, LED Scroller, Food Cal AI - share one set of services: Unity LevelPlay mediation with Google AdMob, Unity Ads, ironSource Ads, AppLovin, Meta Audience Network and Mintegral for ads, and GameAnalytics for analytics. Food Cal AI also uses OpenAI and Open Food Facts (see "AI processing").

Chart AI uses Firebase Analytics, and OpenAI through a Cloudflare Worker for chart analysis. It shows no ads.

HabitKeep uses Google AdMob with Google's consent platform, Firebase Analytics and Apple iCloud (CloudKit) sync. PDF Go uses Google AdMob with Google's consent platform, Firebase Analytics and Crashlytics, and Apple iCloud Drive.

Document Scanner uses no third-party services at all: no ads, no analytics and no tracking.

Each app's own website has a privacy policy that describes that app in full.

Camera, microphone and photos

Document Scanner and PDF Go use the camera only to scan documents, through Apple's VisionKit on your device. Chart AI and Food Cal AI use it, or your device's photo picker, only when you take or pick a picture to analyse. LED Scroller uses the camera flash only as a light and never takes pictures. Speaker Cleaner uses the microphone only on your device for its noise meter; nothing is recorded or uploaded. Where an app lets you pick photos, sounds or files, it sees only what you pick.

Apple Health and Calendar (HabitKeep)

HabitKeep can read the Apple Health data types you choose, only to fill in your progress on the habits you connect to them. It never writes to Apple Health. Health data is never sent to me or to any third party and is never used for advertising, marketing or data mining.

With your permission, HabitKeep adds habit reminders to its own calendar and reads the events in your other calendars to show them next to your tasks. Calendar data stays on your device.

Face ID (Document Scanner)

Document Scanner can lock documents with Face ID. Face ID is handled by iOS: the app only learns whether you were recognised, and never has access to your face data.

AI processing

Chart AI. When you ask the app to analyse a chart, the app sends the chart images you chose (resized, up to four per analysis), your trading preferences (market, risk level, trading style and analysis depth) and the app's language to OpenAI (model gpt-4o-mini) in order to produce the technical analysis shown in the app. The request goes through a Cloudflare Worker that I operate, which forwards it to OpenAI and does not store the images or the result. Cloudflare sees your IP address when it delivers the request, and the worker uses it only to limit how many analyses can be requested per minute. No name, email address, account or device identifier is sent.

The analysis is generated automatically, can be wrong, and is for information and education only. It is not financial advice or a recommendation to buy or sell anything.

Food Cal AI. When you photograph a meal or a food label, pick a photo, scan a barcode or describe a meal in words, the app sends the photo (cropped and resized), the product name found for the barcode, or the text you typed, together with the app's language to OpenAI (model gpt-4o-mini) in order to estimate the food's calories and nutrients. The request goes directly from your device to OpenAI. Your profile - name, age, gender, height and weight - is never sent. A scanned barcode is first looked up on Open Food Facts, a free public food database, which receives only the barcode number.

Calorie and nutrient values are estimates. They can be wrong, especially for mixed or home-cooked dishes, and they are not medical, dietary or nutritional advice. Talk to a doctor or a registered dietitian before making decisions about your diet or health, especially if you have a medical condition, are pregnant or have a history of eating disorders.

This only happens when you ask for it; nothing is sent for AI processing in the background, and what is sent is used only to produce your result. According to OpenAI's API data usage policy, data sent through OpenAI's API is not used to train OpenAI's models; OpenAI may keep it for a limited period to monitor for abuse, as described in its privacy policy. Please do not include personal details you do not want to share, such as names or account numbers, in what you send.

Notifications

Most of the apps can, with your permission, schedule local notifications on your device - reminders, occasional tips, and a reminder before a free trial ends. They are created and delivered by your device itself, no data is sent to me to do this, and you can turn them off at any time in your device's notification settings.

Log Data

I want to inform you that whenever you use my Service, in a case of an error in the app I collect data and information (through third party products) on your phone called Log Data. This Log Data may include information such as your device Internet Protocol ("IP") address, device name, operating system version, the configuration of the app when utilizing my Service, the time and date of your use of the Service, and other statistics.

Cookies

Cookies are files with a small amount of data that are commonly used as anonymous unique identifiers. These are sent to your browser from the websites that you visit and are stored on your device's internal memory. This Service does not use these "cookies" explicitly. However, the app may use third party code and libraries that use "cookies" to collect information and improve their services. You have the option to either accept or refuse these cookies and know when a cookie is being sent to your device. If you choose to refuse our cookies, you may not be able to use some portions of this Service.

Service Providers

I may employ third-party companies and individuals due to the following reasons:

I want to inform users of this Service that these third parties have access to your Personal Information. The reason is to perform the tasks assigned to them on our behalf. However, they are obligated not to disclose or use the information for any other purpose.

Security

I value your trust in providing us your Personal Information, thus we are striving to use commercially acceptable means of protecting it. All data the app sends to the services above is encrypted in transit. But remember that no method of transmission over the internet, or method of electronic storage is 100% secure and reliable, and I cannot guarantee its absolute security.

Responsible Disclosure Policy

We take the security of our systems and data seriously. If you believe you have discovered a vulnerability, please follow these guidelines:

  1. Do not exploit the vulnerability beyond what is necessary to confirm its existence.
  2. Do not access, modify, or delete data that does not belong to you.
  3. Report the issue to the website owner with details so we can reproduce the finding.
  4. We will acknowledge receipt and work to address the issue as quickly as possible.
  5. Testing is only authorized within the scope of this policy. Any testing outside of scope may be considered unauthorized and could be subject to legal action.
  6. We are not responsible for any damage, loss, or impact to your devices, systems, or data at any time, whether or not it is related to security testing.

Links to Other Sites

This Service may contain links to other sites. If you click on a third-party link, you will be directed to that site. Note that these external sites are not operated by me. Therefore, I strongly advise you to review the Privacy Policy of these websites. I have no control over and assume no responsibility for the content, privacy policies, or practices of any third-party sites or services.

This website

The website this policy is published on is hosted by Vercel, which processes standard server logs (such as your IP address, browser and the page requested) to deliver and protect the site. I count visits with Umami, an analytics tool I host myself: it does not use cookies, does not follow you across other websites and does not store your IP address. It records the page visited, the referring site, your browser, device type and country, and clicks on a few links such as the store buttons.

If you sign up for the newsletter, the only thing I ask for is your email address. It is sent to and stored by Brevo, the service I use to send the newsletter, and is used for nothing else. Every email has an unsubscribe link, and you can unsubscribe at any time.

A few older pages of dczt.dev, kept from the previous version of this site (the individual app pages, the old FAQ and the changelog), still load Google Analytics, which uses cookies and receives your IP address, browser and the pages you visit, as described in Google's privacy policy.

Children's Privacy

These Services do not address anyone under the age of 13. I do not knowingly collect personally identifiable information from children under 13, and the app never asks for a name, email address or other contact details. If you are a parent or guardian and believe that your child has provided personal information, or that one of the services listed above has collected it, please contact me at support@dczt.dev so that I can have it deleted.

Your Rights and Data Deletion

Depending on where you live, you may have the right to access, correct, delete or export the personal data held about you, to object to or restrict its processing, and to withdraw consent.

DCZT apps has no accounts and I do not run servers that store personal data about you, so there is no account or server copy for me to delete. The data the app keeps on your device is deleted when you delete the app. Anything kept in your own iCloud account stays there until you delete it, which you can do in your device's iCloud settings. Resetting your advertising identifier in your device settings breaks the link between your device and any advertising profile.

For data held by the third-party services listed above, you can make a request to each of them directly through the privacy policy linked next to its name. You can also email me at support@dczt.dev with your request: I will pass it on to the services concerned and confirm when it is done.

To have your email address removed from the newsletter, use the unsubscribe link in any email or write to me. You also have the right to lodge a complaint with your local data protection authority.

Changes to This Privacy Policy

I may update our Privacy Policy from time to time. Thus, you are advised to review this page periodically for any changes. I will notify you of any changes by posting the new Privacy Policy on this page.

This policy is effective as of 2026-09-27

Contact Us

If you have any questions or suggestions about my Privacy Policy, do not hesitate to contact me at support@dczt.dev.

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