Privacy Policy for SysCraft: System Design (HLD)
1. Overview & Applications Covered
This Privacy Policy describes how MedTech Labs handles information in connection with the application SysCraft: System Design (HLD) (referred to in this document as "the Application" or "the Service").
This policy applies exclusively to SysCraft: System Design (HLD) across its supported platforms (android, ios) with Android Package identifier: com.syscraft.app.
2. Developer & Publisher Identity
The Application is published and operated by:
- Publisher / Organization: MedTech Labs
- Legal Entity: MedTech Labs
- Official Website: https://instantbiodata.in
- Dedicated Privacy Contact: medtech.publisher@gmail.com
3. Information Collection & Practices
Below is the verified inventory of data practices and permissions processed in connection with SysCraft: System Design (HLD):
No Remote Data Collection
Processed Locally OnlyThe application functions completely on-device without collecting or transmitting user data to external servers.
Data Types: No personal identifiers, No location data, No biometric data
User Control: You can clear locally stored app data at any time via your device settings.
Payment Processing & Order Fulfillment
Encrypted TransmissionSysCraft offers an optional one-time digital in-app purchase ('SysCraft Lifetime Pass' — ₹150 INR / ~$1.99 USD) to unlock advanced High-Level Design (HLD) and Low-Level Design (LLD) curriculum modules. All financial transactions and payment processing are handled exclusively and securely by the Google Play Store via the official Google Play In-App Billing API. The developer never receives, accesses, or stores your credit card numbers, bank account details, UPI credentials, or billing addresses.
Data Types: Order reference ID, Transaction status, Billing email / phone number
User Control: Card numbers and bank credentials are handled directly by PCI-DSS certified payment gateways and are never stored on our servers.
Local On-Device Storage
Processed Locally OnlyAll curriculum progress, lesson completion states across HLD and LLD modules, active domain selections, reading mode preferences (ELI10 Mode vs Deep Engineering Mode), typography scaling, dark/light theme choices, and hardware-backed receipt tokens are stored strictly within your local device's isolated application sandbox.
Data Types: Completed curriculum lesson IDs and topic mastery statistics across 10 modules, Active curriculum domain preference (High-Level Design vs Low-Level Design), Reading mode preference (ELI10 Analogy Mode vs Deep Engineering Mode), Appearance theme selection (Paper Light, OLED Dark, System Default), Reading text font scale factor (85% to 130%), Cryptographically signed entitlement receipt stored in hardware-backed storage (expo-secure-store / Android Keystore)
User Control: Users can delete all stored data by resetting app data in device settings.
Haptic Feedback (android.permission.VIBRATE)
Processed Locally OnlyUsed strictly on-device to provide subtle tactile mechanical confirmation when toggling between ELI10 and Deep Engineering reading modes or adjusting typography scale. Zero haptic or device interaction data is logged, retained, or transmitted.
Data Types: Tactile vibration actuator state
User Control: Haptic feedback can be managed or silenced via Android system sound and vibration settings.
Network State & Google Play Billing Connection (android.permission.INTERNET)
Encrypted TransmissionRequired strictly and exclusively by the Google Play In-App Billing client library to communicate with Google Play servers to validate purchase tokens and activate the one-time Lifetime Pass. SysCraft contains zero cloud telemetry endpoints, zero tracking beacons, and zero remote curriculum servers.
Data Types: Cryptographic purchase token state validated with Google Play APIs
User Control: Digital orders and subscriptions are managed directly through your Google Play Store account.
4. Third-Party Services & SDKs
To provide essential functionalities such as secure in-app digital purchases and billing fulfillment, SysCraft: System Design (HLD) integrates the following third-party software development kits (SDKs):
| Service / SDK | Provider | Primary Purpose | Official Links |
|---|---|---|---|
| Google Play In-App Billing | Google LLC | Processing in-app purchases and managing premium feature entitlements; Validating digital purchase receipts with Google Play APIs | Privacy Policy ↗|Docs ↗ |
5. In-App Purchases & Google Play Billing
If you purchase digital products, premium templates, or watermark-free exports within SysCraft: System Design (HLD), all financial transactions and order fulfillments are handled directly by Google Play In-App Billing.
We never receive, collect, or store your credit/debit card details, bank information, or billing addresses. Purchases are tied securely to your Google Play Account and governed by the Google Play Terms of Service and Google Privacy Policy.
6. Analytics & Technical Diagnostics
To ensure high operational stability, crash prevention, and optimal performance across device form factors, technical diagnostics and basic operational telemetry may be processed during app execution. These diagnostics do not contain user identities or sensitive personal documents.
7. User Accounts & Registration
SysCraft: System Design (HLD) does NOT require registration, login, or user account creation. The Application functions entirely without user accounts, authentication profiles, or login credentials.
8. Data Retention Policy
All curriculum progress, lesson completion states, reading preferences, and hardware-backed receipt records are stored 100% locally on your physical device. We operate zero cloud servers, user accounts, or remote databases. Google Play In-App Billing purchase tokens and order state are managed directly by Google LLC under standard Google Play retention schedules.
Retention Criteria: Local course mastery and reading settings persist on-device until manually cleared by the user via device settings or upon application uninstallation. Digital billing receipts are linked to your Google Play account.
Backup & Storage Scope: Zero transmission of curriculum reading progress, user notes, or personal telemetry to external servers; no cloud backups or remote archives are maintained by the developer.
9. Data Deletion & User Control Rights
In compliance with Google Play User Data policies and international privacy standards, users have clear control over their data:
How to Delete Data: Because all lesson progression, reading mode preferences, font scaling, and cryptographic receipts reside entirely within sandboxed local device storage (AsyncStorage and Android Keystore via expo-secure-store), you can permanently delete all local data immediately at any time by clearing application data via Android Settings (Settings > Apps > SysCraft > Storage > Clear Data) or by uninstalling the application. Since no user accounts or cloud databases exist on our servers, no remote personal data deletion request is required.
Online Deletion Request: https://instantbiodata.in/privacy/syscraft#contact
Email Submission: Send an inquiry with subject "Data Deletion Request - SysCraft: System Design (HLD)" to medtech.publisher@gmail.com.
Processing Timeline: Requests are processed within Immediate for on-device data; within 30 days for customer support inquiries.
10. Children's Privacy (COPPA & Google Play Families Policy)
General Audience Application: SysCraft: System Design (HLD) is an educational reference application engineered for software engineers, backend developers, computer science students, and technical interview candidates aged 13 and older. The Application is not directed toward children under 13.
We do not knowingly solicit or collect personal information from children under 13 years of age.
SysCraft does not knowingly collect personal identifiable information from children under 13. The application operates with a 100% offline-first architecture, requires zero accounts or email registrations, contains zero ads, and processes all reading progress and system design curriculum data strictly on the local physical device.
If you are a parent or guardian and believe your child has provided us with personal information without appropriate consent, please contact us immediately so we can promptly take corrective action.
11. Data Security & Protection
We employ industry-standard administrative, physical, and technical safeguards designed to protect your information from unauthorized access, alteration, or disclosure:
- 100% Offline-first local architecture ensuring curriculum reading history and topic completion metrics never leave your physical device
- Hardware-backed cryptographic storage (expo-secure-store utilizing Android Keystore / iOS Keychain) for lifetime pass receipt validation
- Standard Android application sandboxing isolating course progress and preferences from unauthorized third-party apps
- Zero integration of third-party advertising SDKs, behavioral analytics suites, or user tracking cookies
- All digital purchase operations executed exclusively through Google Play In-App Billing utilizing PCI-DSS Level 1 compliant Google infrastructure with TLS encryption
12. Changes to this Privacy Policy
We may periodically update this Privacy Policy to reflect changes in software features, platform SDKs, or regulatory requirements. Any modifications will be posted to this page with an updated revision date.
Last reviewed and updated: 2026-11-04.
13. Contact Information
If you have questions, feedback, or privacy-related requests concerning SysCraft: System Design (HLD), please contact our privacy team: