Privacy Policy — SZ Thermometer
Effective date: 2026-09-08
This policy covers the Android application SZ Thermometer
(package name com.vlesu.szthermometer), developed by Arsenii Kurin
(asen.vlesu.com).
Summary
SZ Thermometer does not collect, store, or transmit any personal data. It has no account system, no analytics, no advertising, and no network connection of any kind — the only external communication the app performs is a local Bluetooth link to an OBD2/ELM327 adapter that the user themselves selects and pairs, plugged into their own vehicle.
What data the app handles, and where it lives
Everything the app remembers stays only on your device, in the app's private local storage (Android DataStore). None of it is sent to us, to the app developer, or to any third party — the app has no server to send it to.
This local-only data includes:
- The Bluetooth address and name of the OBD2 adapter you selected, so the app can reconnect to it automatically.
- Your chosen alarm thresholds (gearbox/engine temperature, minimum battery voltage), poll interval, and unit preference (°C/°F).
- Overlay widget preferences: which values to show, its position on screen, opacity, font size, and label text.
- Interface language preference.
None of this is personally identifying beyond the fact that it describes your own vehicle's Bluetooth adapter and your own preferences. It is never uploaded, backed up to the cloud (the app explicitly disables Android's automatic cloud backup for its data), or shared with anyone. Uninstalling the app permanently deletes all of it.
Bluetooth data
The app reads live diagnostic values (gearbox temperature, engine coolant temperature, battery voltage) from your vehicle's OBD2 adapter over a direct Bluetooth connection between your phone and that adapter. These readings are shown to you in the app (and optionally in the on-screen overlay) and are not stored beyond the current session, not logged to a file, and not transmitted anywhere.
Permissions the app requests, and why
| Permission | Why it's needed |
|---|---|
Bluetooth (BLUETOOTH_CONNECT, and legacy
BLUETOOTH/BLUETOOTH_ADMIN on older Android) |
To connect to the ELM327 adapter you select and exchange diagnostic commands with it. |
| Foreground Service / Foreground Service (Connected Device) | To keep monitoring your vehicle's readings reliably while you drive, even while the app is in the background. |
| Post Notifications | To show the ongoing "monitoring active" status notification (low-priority, does not pop up or make sound by itself). |
Display over other apps (SYSTEM_ALERT_WINDOW) |
Optional: powers the floating overlay widget that can show live readings on top of other apps (e.g. a navigation app) while driving. Only active if you enable it in Settings and grant the permission. |
The app requests no location, camera, microphone, contacts, storage, or any other permission beyond what's listed above.
Third parties
The app contains no third-party SDKs, analytics libraries, advertising libraries, or crash-reporting services. No data is shared with any third party because none is collected in the first place.
Children's privacy
The app is a vehicle-diagnostics utility not directed at children and does not knowingly collect any data from anyone, including children.
Changes to this policy
If this policy ever changes, the effective date above will be updated accordingly.
Contact
Questions about this policy or the app can be sent via asen.vlesu.com.