Privacy Policy

Overview

Rook Calculator (“the App”) is an Android RPN calculator developed and published by Rook Software. This policy explains exactly what data the App handles, how it is stored, and what network communication occurs. The short version: your calculations stay on your device, and we do not collect any personal information.

Data Collection

Specifically, the App:

• Does not collect personal information
• Does not track your location
• Does not access your contacts, photos, or files (the export/import feature uses Android's file picker, which you control)
• Does not require any Android permissions
• Does not use analytics, crash reporting, or tracking services
• Does not contain advertisements

All calculations are performed entirely on your device. Your calculation history, stored values, and programs remain on your device and are never shared.

Android Permissions

Rook Calculator does not request any Android permissions. The App does not access your camera, microphone, contacts, files, location, or any other device capabilities beyond its own private storage area.

Data Storage

The App stores the following data locally on your device only:

• Display settings — display mode (FIX/SCI/ENG/ALL), decimal places, number format, thousands separator, decimal separator, and digit grouping
• Calculator mode — RPN or algebraic (ALG) mode selection
• Angle mode — degrees, radians, or gradians
• Complex number mode and fraction display mode states
• RPN stack contents — the four stack registers (T, Z, Y, X) and the LASTx value
• Storage registers — variables A through Z (26 registers)
• Statistics data — entered X and Y data point lists
• Calculator flags — 12 flags (5 user flags and 7 system flags)
• Saved equations — user-created equations stored by ID
• User programs — programs labeled A through Z, up to 800 total program lines
• Keyboard layout preference and compact label display setting
• Stack display preference (full 4-register or compact 2-register view)
• Haptic feedback intensity preference (off, light, or full)
• Theme mode preference (system, light, or dark)
• Calculation history — operation log with timestamps, categories, operation names, and input/output values (stored in a local database, configurable limit up to 50,000 entries)
• History settings — logging enabled/disabled, maximum entry count, and maximum age

This data is stored in the App's private storage area and is automatically deleted if you uninstall the App.

This App supports Android's built-in backup feature, which may back up all of your calculator data—including settings, stack state, variables, equations, programs, calculation history, and display preferences—to your personal Google account. This includes both cloud backup to Google Drive and device-to-device transfer when switching phones. This backup is managed entirely by Google and your device settings. Rook Software does not have access to your backed-up data. You can disable backup for this App in your device's Settings under Apps → Rook Calculator, or manage backed-up data through your Google Account at myaccount.google.com.

Settings and calculator state are stored using Android's SharedPreferences in the App's private storage. Five separate preference files are used: one for calculator settings, one for calculator state (stack, variables, statistics, and flags), one for equations, one for programs, and one for display preferences. Calculation history is stored separately in a local SQLite database.

The calculation history log records each operation you perform, including a timestamp, operation category (math, stack, memory, equations, etc.), operation name, formatted input and output values, and contextual information where applicable (such as the equation string for equation operations). History entries contain only calculator operations and numeric values—no personal information. History is automatically pruned based on your configured limits (default 5,000 entries, no age limit). You can disable history logging entirely in Settings.

When you use the Share feature to export equations, the App creates a temporary file in its private cache directory. This file is shared with the app you select (email, cloud storage, etc.) using Android's FileProvider, which grants temporary read-only access to that single file. The temporary file is automatically cleaned up by Android. The FileProvider is not accessible to other apps except during an active share you initiate.

Equation Export & Import

The App allows you to export your saved equations as a JSON backup file and import equations from a backup file. This feature is entirely user-initiated and uses Android's Storage Access Framework (SAF), which presents a system file picker that you control. The App does not require any storage permissions for this feature.

Export (Save to File): When you choose to save a backup, Android's file picker lets you select where to save the file. The App writes the JSON file to that location and has no further access to it. The exported file contains only your equation expressions and their numeric IDs—no personal information.

Export (Share): When you choose to share a backup, the App creates a temporary file and opens Android's Share Sheet so you can send it to an app of your choice (email, cloud storage, messaging, etc.). The destination app receives only the equation data.

Import: When you choose to import, Android's file picker lets you select a JSON backup file. The App reads the file, validates it, and adds the equations to your local storage. The App does not retain access to the file after import.

No data from this feature is transmitted to Rook Software or any third party. The export/import process happens entirely between your device and the destination you choose.

Network Communication

The App communicates over the internet solely for Google Play license verification. This check confirms that your copy of the App was obtained through the Google Play Store. The license check is handled entirely by Google Play services and does not transmit any of your calculator data, calculation history, settings, or personal information to Rook Software or any third party.

No other network communication occurs. The App does not phone home, check for updates independently, or transmit usage data of any kind.

Third-Party Services

The only third-party service integrated into the App is Google Play Licensing, which verifies your purchase through the Google Play Store. This service is provided by Google and is subject to Google's Privacy Policy (https://policies.google.com/privacy). Rook Software does not receive any personal data from this service.

The App does not integrate any analytics services, advertising networks, crash reporting tools, or social media SDKs.

Children's Privacy

The App does not collect any personal information from anyone, including children under the age of 13.

Data Deletion

Since all data is stored locally on your device, you have full control over it at all times. There are several ways to manage your data:

CLALL (Clear All): Available from the App's Clear menu, this resets the stack, variables, statistics, programs, and flags to their default state. Saved equations, calculation history, and your display and calculator mode preferences are preserved.

Clear History: The history panel provides options to clear all calculation history or delete individual entries. This does not affect any other calculator data.

Clear Data via Android Settings: Going to Settings → Apps → Rook Calculator → Storage → Clear Data will delete all locally stored App data, including settings, equations, programs, and calculation history. This is a complete reset.

Uninstall: Removing the App deletes all locally stored data, including the history database. If you have Android backup enabled, backed-up data can be managed or deleted through your Google Account settings.

Changes to This Policy

We may update this Privacy Policy from time to time. Any changes will be posted on this page with an updated revision date. Continued use of the App after changes constitutes acceptance of the updated policy.