cMatriX app — privacy policy

Who is responsible

The cMatriX mobile app is published by cMatriX, Estonia. Questions about your data: info@cmatrixpro.com

This policy covers the cMatriX app for iPhone. The website has its own privacy notice.

The short version

The app has no user accounts, no analytics, no advertising and no tracking. Your projects and measurements stay on your phone. The only data that leaves your phone is your approximate position, sent to a weather service so the app can show the air temperature at your site — and only if you allow location access.

Data stored on your phone

The app stores the following only on your device:

• Projects you create (name, pour date, concrete class, cement type and other mix details you enter)
• Concrete recipes and calibration values you enter
• Temperature measurements read from your cMatriX sensors, and the maturity and strength values calculated from them
• The names and identifiers of sensors you have paired

This data is not sent to us or to anyone else. We cannot see it. It is deleted when you delete a project in the app or remove the app from your phone.

Bluetooth

The app uses Bluetooth to connect to cMatriX sensors: it reads the temperature log from the sensor and sends project settings (time, cement type, target strength) to it. This is a direct connection between your phone and your sensor. No Bluetooth data passes through the internet.

Location

If you allow it, the app uses your location while the app is open to show the outdoor air temperature, weather and frost warnings for your construction site next to the strength forecast.

To do this, the app sends your device's current coordinates to Open-Meteo, a free weather service, and receives the forecast back. The request contains only the coordinates — no name, account, device identifier or project data. The app does not store your location, and we do not receive it. Open-Meteo's handling of requests is described in its terms and privacy information.

Location is optional. If you deny access, everything else in the app works; only the weather information is not shown. You can change this at any time in iPhone Settings → Privacy & Security → Location Services → cMatriX.

Reports

PDF reports are created on your phone. They are shared only if you choose to print, save or send them yourself.

What we do not do

• We do not collect personal data through the app
• We do not use analytics, crash reporting, advertising or tracking tools
• We do not sell, rent or share data
• We do not track you across other apps or websites

Children

The app is a professional tool for construction work and is not directed at children.

Your rights

Because the app does not send us your data, we hold no app data about you. You control everything stored on your phone and can delete it at any time. Under the GDPR you still have the right to ask us about any data we hold — write to info@cmatrixpro.com and we will respond within one month. You can also complain to the Estonian Data Protection Inspectorate (Andmekaitse Inspektsioon, www.aki.ee).

Changes

If the app starts handling data differently — for example cloud backup or data sharing between team members — this policy will be updated before that change is released, with a new date on this page.