Privacy Policy: HVAC Calculator & PT Chart

Effective 27 September 2026. Published at https://apps.digitalshijil.com/hvac-calc/privacy/

HVAC Calculator & PT Chart ("the app") is published by DIGITAL SHIJIL LLC. This policy explains what the app does with information. The short version: the readings you type stay on your phone.

What the app stores, and where

• Your readings and jobs. Gauge pressures, line temperatures, airflow, duct, electrical and psychrometric inputs, the jobs you save them to, job notes, and your settings are stored only in the app's private storage on your phone. We have no server and no account system, so we never receive them.
• Files you create. Job PDFs and the data export are written to the app's private cache and leave the phone only if you share them yourself, through the Android share sheet, to an app you choose.
• Backups. If you have Android backup turned on, your jobs, readings and settings are included in your own Google backup and device-to-device transfer, under your Google account. We cannot read that backup.

What the app does not do

• No account, no sign-in, no email collection.
• No advertising, no advertising ID, no analytics or crash-reporting SDK.
• No Bluetooth gauge connection, location, camera, contacts, microphone, storage or notification permission. The app itself declares no Android permission at all.

Google Play Billing

The optional one-time Pro unlock is sold through Google Play. Google processes the payment; we never see your card or payment details, only whether Pro is owned. To do this, Google's Play Billing library is part of the app and brings in the INTERNET, ACCESS_NETWORK_STATE and com.android.vending.BILLING permissions. The Play Billing library also sends Google diagnostic information about billing operations (for example whether a connection or a purchase check succeeded). We declare this on the Play Store Data safety form as:

App info and performance > Diagnostics: collected, not shared, required

This diagnostic data goes to Google under Google's own privacy policy (https://policies.google.com/privacy). It does not include anything you type into the app, and we cannot view or delete it.

Your control

• Export all my data (Settings) writes everything the app stores into one readable JSON file you can keep or share.
• Delete all data (Settings) erases every job, saved reading and setting from the phone, returning the app to a fresh install. A Pro purchase belongs to your Google account and is restored by Google Play.
• Uninstalling the app removes all of its data from the phone.

Children

The app is a trade tool for adults and is not directed at children.

Accuracy and safety

The app is a calculation aid only. It makes no certification or compliance claim. Handling refrigerant requires the certification your region demands, such as EPA Section 608 in the US. Every job PDF is marked: For personal record-keeping. Not an official document.

Changes and contact

If this policy changes, the new version is published at the address above with a new effective date. Questions: contact@digitalshijil.com