Privacy Policy for 555 Timer Calc

Introduction

555 Timer Calc ("the App") is a professional and educational mobile application developed by AntoTech ("we," "us," or "our"). This Privacy Policy explains how we handle your information when you use the App. The App is a high-precision analog electronics simulator designed for students, electronic engineers, and hobbyists. It offers real-time calculation for NE555 circuits in Astable, Monostable, and PWM modes, dynamic waveform analysis, component color code visualization, a reverse design assistant, and an optional Pro tier with advanced tolerance analysis, PDF export, and saved design history.

By using the App, you agree to the collection and use of information in accordance with this policy. The App’s core calculation engine operates 100% offline, performing all mathematical, logical, and signal processing locally on your device — we never transmit your circuit values, design suggestions, or Bill of Materials (BOM) data to our servers. However, certain optional features of the App — namely advertising (free version), in-app purchases, consent management, and update checks — require an internet connection and involve limited data exchange with the third-party services described below.

Information We Collect

1. Information You Provide

•     Component Values for Simulation: When you input values for resistors (R1, Ra, Rb) or capacitors (C), the data is processed in real-time locally to generate frequency, duty cycle, and period results. This information exists only in the active state and is not stored beyond your current session unless saved via local cache.

•     Design Assistant Inputs: Data generated during the Reverse Design mode (Target Frequency, Target Time, and any custom capacitor values you add to your personal "Junkbox") is processed locally to provide commercial component suggestions.

•     Saved Design History: If you choose to save a circuit configuration — the component values and an optional name you provide — it is stored locally on your device via localStorage. This data is never transmitted to us or to any third party, and you can delete saved designs at any time from within the App.

•     Persistence: To allow you to resume your work, your most recent component values, selected E-Series, and calculation results are stored locally on your device using localStorage.

2. Hardware and System Access

•     Social Sharing & Clipboard API: The App accesses the device’s sharing system and clipboard only when you explicitly trigger the "Generate BOM," "Export CSV," "Export PDF," or "Export SPICE Netlist" functions. This is used to transfer your results to external apps of your choice.

•     Storage Access: The App uses local browser storage (localStorage) to maintain your preferences (Language, Component Values, Series Selection, Pro purchase status) without requiring external file system permissions.

•     No Camera/Microphone Usage: The App DOES NOT require or use the camera or microphone. All interactions are performed via manual digital and slider inputs.

3. Automatically Collected Information

•     Device and Usage Data: The App may utilize non-personal information (device model, screen resolution) to ensure compatibility and performance optimization across different mobile displays.

•     Advertising Identifiers (Free version only): In the free version, Google AdMob may collect device identifiers (such as your Advertising ID), IP address, and general device/network information to serve and measure ads. See "Advertising & Consent Management" below for full detail.

Local Preferences: We use localStorage to remember your settings, such as:

•     Language preference (English/Spanish).

•     IC family and technology (Bipolar/CMOS — NE555, NE556, LMC555, TLC555, ICM7555).

•     E-Series preference (E12/E24).

•     Last used calculation mode and Pro purchase status.

4. In-App Purchases

When you purchase 555TimerCalc Pro, the transaction itself is handled entirely by Google Play Billing. We do not collect, see, or store your payment details (such as credit card numbers or billing address) — that information is processed directly by Google under Google’s own Privacy Policy and Payments Privacy Notice. We only receive a purchase confirmation, which is used to unlock Pro features locally on your device.

5. Advertising & Consent Management (Free version only)

The free version of the App displays advertisements served by Google AdMob (a service of Google LLC). To provide and measure these ads, AdMob may collect and process:

•     Device identifiers, such as your Advertising ID.

•     IP address and general device/network information.

•     Ad interaction data (impressions, clicks).

If you are located in the European Economic Area, the United Kingdom, or Switzerland, the App will present a consent form (via Google’s User Messaging Platform) before requesting personalized ads, allowing you to choose whether to allow personalized advertising. You can review or change your ad preferences at any time through your device’s own ad settings (Android Settings > Google > Ads).

For details on how Google collects and processes this data, please review Google’s Privacy Policy (policies.google.com/privacy) and Google’s Ad Technology Providers page (policies.google.com/technologies/partner-sites).

Purchasing 555TimerCalc Pro removes all advertising from the App entirely.

6. App Update Check

On each launch, and whenever you manually check for updates in Settings, the App fetches a small, non-personal configuration file from a publicly hosted file we maintain, to determine whether a newer version of the App is available. This request does not include any personal information beyond what is inherent to a standard network request (such as your IP address, which is not logged or stored by us).

How We Use Your Information

•     To Provide App Functionality: To calculate electronic parameters, generate signal waveforms using Recharts, and provide estimated power consumption.

•     Technical Warnings: To provide local, rule-based alerts (e.g., high frequency, extreme duty cycle, or power dissipation warnings) based on your inputs.

•     BOM, PDF & Netlist Generation: To format your circuit data into a sharable Bill of Materials, PDF design report, or SPICE netlist for your physical builds and simulations.

•     To Process In-App Purchases: To unlock Pro features once Google Play confirms your purchase.

•     To Display and Measure Advertising: Via Google AdMob, in the free version only, as described above.

•     To Check for App Updates: To notify you when a newer version of the App is available.

Sharing of Information

•     Third-Party Service Providers: We work with the following third-party services to operate parts of the App: Google AdMob (advertising, free version only), Google Play Billing (in-app purchases), and Google’s User Messaging Platform (consent management, EEA/UK/Switzerland). These providers process data as described in their own privacy policies, linked above. We do not sell your data to anyone.

•     User-Triggered Sharing: Information is shared with third parties only when you explicitly use the "Share" or "Export" functions (BOM, CSV, PDF, SPICE Netlist) to send data via your preferred email, messaging, or cloud apps.

•     Legal Requirements: We do not store personal data or calculation history on our servers; therefore, we have no data to provide to third-party authorities beyond what Google independently processes for billing and advertising, as described above.

Data Security

•     Local Processing: All mathematical processing occurs strictly on your device.

•     Local Storage: Be aware that saved preferences and design history stay on the device. If you uninstall the App or clear your app cache, this data will be permanently deleted.

•     Third-Party Processing: Data handled by Google (advertising, purchases, consent management) is processed and secured under Google’s own security practices and policies.

•     Physical Security: We recommend securing your device with a PIN, pattern, or biometric lock to protect your local design configurations.

Children’s Privacy

The App is a tool intended for students and electronics enthusiasts and is not directed at children under 13. We do not knowingly collect personal information from children under 13, and the App does not feature user accounts or cloud synchronization. Please note that the free version of the App displays advertising served by Google AdMob. If you believe a child has provided us with personal information, please contact us using the details below so we can address it.

Your Rights and Choices

•     Access and Control: You have full control over your data. You can change your settings, delete saved designs, or reset component values directly within the App interface.

•     Ad Preferences: You can manage or opt out of personalized advertising at any time via your device’s ad settings, or by purchasing 555TimerCalc Pro to remove ads entirely.

•     Purchase Restoration: If you reinstall the App or switch devices, you can restore your Pro purchase at any time from the Settings screen, at no additional cost, provided you are signed in to the same Google Play account.

•     Data Deletion: Simply clearing the App data in your device settings or uninstalling the App will remove all locally stored preferences and saved designs.

Changes to This Privacy Policy

We may update this Privacy Policy to reflect changes in our practices or for legal reasons. The updated version will be accessible within the App settings.

Contact Us

If you have questions regarding this Privacy Policy, please contact us at:

Email: tech.anto19@gmail.com