SparkCalcPrivacy Policy
1. Who we are
SparkCalc is published by Eric Z (“we”). Contact: candy66861@gmail.com.
2. Data that stays with you
- Calculations, saved calculations, answers, study progress, bookmarks, exam plan and settings are stored on your device.
- iCloud sync (on by default, can be turned off in Settings) stores this data in your own private iCloud database. Apple handles it under Apple's privacy policy; we cannot access it.
- Things you copy, share or export go only where you send them.
3. Data we collect
3.1 Anonymous usage statistics (you can turn this off)
We record events such as “calculator opened”, “practice set finished” or “mock exam submitted”, with coarse details such as the calculator type, the standard (NEC / JIS / KEC), a count or a score range. Each event includes a random installation ID created by the app (it changes if you reinstall), app version, iOS version, device model, language, region and time zone.
We never collect the values you enter or the results, the names or notes of saved calculations, your answers' text, search terms or the text of problem reports. We do not collect your name, email address or the advertising identifier (IDFA).
Purpose: learning which features are used so we can improve the app. Turn it off at any time in Settings (“Share anonymous usage statistics”). Raw events are kept for 90 days; daily totals without any ID are kept for 400 days.
3.2 Crash reports
If the app crashes, Firebase Crashlytics (Google) receives a crash report: stack trace, app version, iOS version, device model, free memory and storage, and a Crashlytics installation ID. We use it only to fix bugs. It is turned off together with usage statistics.
3.3 Diagnostic logs
The app keeps a short technical log on your device (for example content download status) for up to 7 days. It never contains your calculations or answers. Only when we investigate a problem can we ask the app to upload this log for a specific installation ID. Uploaded logs are deleted within 90 days. No logs are uploaded while statistics are turned off.
3.4 Exam content updates
The app checks our server spark-calc-api.koelearn.com for corrections and new exam content (for example the new year's candidate problems). The request contains only the exam track, the app version and the content version you have. It contains no personal data.
3.5 Problem reports (only when you send one)
If you tap “Report a problem” on a question or calculator, we receive: which item it is, the reason you chose, the optional text you write (up to 300 characters), the app and content version, your language setting, and a one-way code derived from the installation ID that changes every day (used only to stop spam, limited to 20 reports a day). Please do not write personal information in the text. Resolved reports are kept for up to 365 days.
3.6 Network data
When the app contacts our server, our hosting provider Cloudflare processes your IP address to deliver the request and protect against abuse. We do not store IP addresses or access logs.
3.7 Purchases
Payments are handled by Apple. We never receive your payment details or Apple Account. The app checks your purchase on the device. Anonymous statistics record that a purchase or restore happened, with the price and currency.
3.8 Support email
If you email us, we receive your email address and what you write. We use it only to answer you and keep support emails for up to 2 years.
4. What we never do
- No advertising and no ad SDKs.
- No tracking across other companies' apps or websites, no IDFA.
- No selling or renting of data, no data brokers, no profiling.
5. Permissions
SparkCalc does not ask for access to your location, contacts, photos, camera or microphone.
6. Service providers and international transfers
| Provider | What for | Data | Location |
|---|---|---|---|
| Cloudflare, Inc. | Content server and database | Problem reports, usage statistics, diagnostic logs | USA and Cloudflare's global network |
| Google LLC (Firebase Crashlytics) | Crash reports | Crash reports | USA |
| Apple Inc. | App Store, purchases, iCloud | Handled under Apple's privacy policy | — |
Data may be processed outside your country. For users in the EEA, the UK and Switzerland, transfers rely on the EU-U.S. Data Privacy Framework and/or the Standard Contractual Clauses offered by these providers.
7. Legal bases (EEA, UK)
Usage statistics, crash reports, diagnostic logs and abuse protection: our legitimate interest in running and improving a reliable app (Art. 6(1)(f) GDPR); you can object at any time by turning statistics off. Problem reports and support: your request (Art. 6(1)(b) GDPR).
8. Your choices and rights
- Turn off anonymous statistics and crash reports in Settings; turn off iCloud sync in Settings.
- Delete data on your device in Settings › Data, or by deleting the app. Data in your iCloud can be deleted in iOS Settings › [your name] › iCloud.
- Because we do not know who you are, we can only find server data by its installation ID. You can copy it in Settings and send it to us to request access or deletion.
- Depending on where you live (for example under the GDPR, California law, Japan's APPI or Korea's PIPA), you may have rights to access, correct, delete, restrict or object to processing and to data portability, and to complain to your data protection authority. We do not sell or share personal information for targeted advertising.
9. Children
SparkCalc is suitable for all ages and collects no personal information from anyone, including children, beyond the anonymous data described above.
10. Security
All connections use HTTPS. Our server holds no calculations, study progress or account data. This website uses no cookies and no third-party scripts.
11. Changes
We will update the date above when this policy changes and mention significant changes in the app's release notes.
12. Contact
Eric Z · candy66861@gmail.com