Nothing.
The app does not collect, store, transmit or share any personal data, usage data, device identifiers, location, or analytics of any kind. It contains no advertising, no analytics library, no crash reporting service, no account system and no server of its own.
Every reading you take is written to the app's own private storage on your device and stays there. Nothing is uploaded, backed up to a cloud, or synchronised anywhere. A reading you delete is gone from the device. Everything is deleted when you uninstall the app.
If you choose to export a survey as a PDF, a PNG or a CSV, the file is written where you tell Android to put it and is under your control from then on. If you choose to share an export, it is handed to the app you pick through the Android share sheet. Sonar itself never uploads it.
Five permissions are declared. All five are granted at install time by Android, and the app asks you for nothing when you open it. The meter, the measurement, the score, the comparison and the report all work without you granting anything.
| Permission | What it is for |
|---|---|
ACCESS_WIFI_STATE | Reading the Wi-Fi link your device is already on: its signal strength, link rate, frequency and standard. |
ACCESS_NETWORK_STATE | Seeing whether Wi-Fi is the active network, and finding the address of your router. |
INTERNET | Timing how long your router takes to answer, during a measurement. This is a packet to your own router on your own network. Nothing is sent to the internet and nothing is sent to us. |
CHANGE_WIFI_STATE | Asking Android for a list of the Wi-Fi networks in range, for the channel graph. |
ACCESS_FINE_LOCATION | Optional, and never requested when you open the app. See below. |
Android treats the names of Wi-Fi networks as location information, because a list of nearby networks can be used to work out roughly where a device is. It therefore hides the name of your own network, the identity of the access point you are connected to, and the whole list of networks in range, from any app that has not been granted location access.
Sonar declares the permission so that you can choose to see those things. It never asks for it at launch and it is never needed for the meter, the measurement, the score, the comparison or the report. You will only be asked if you open the Networks tab and choose to see the networks around you, and the app tells you what granting it unlocks before it asks.
Sonar does not use your location. It does not read GPS, it does not record coordinates, it does not request background location, and it stores no location of any kind. The permission buys the network names back from Android, and nothing else. If you decline it, everything except the network names and the nearby list carries on working.
During a measurement the app sends packets to your router, on your own local network, and times the replies. That is the entire extent of its network activity. It contacts no server of ours, because there is not one, and it contacts no third party. Nothing about you, your device, your network or your measurements is transmitted off your device by the app.
The Send feedback link on this website opens a page carrying a Google Form. Whatever you type into that form goes to Google Forms and is stored there for the maker of the app to read. Your email address is only included if you type it. The app itself sends nothing; the form is a web page you choose to fill in, and Google's own privacy policy applies to it.
This site is served by GitHub Pages and has no analytics, no cookies of its own and no tracking. It loads a web font from Google Fonts, which means your browser makes a request to Google to fetch it; Google's own privacy policy applies to that request.
The app collects no data from anyone, including children.
If this policy ever changes, the change will be noted here with a new date. Any change that involved collecting data would also require a new version of the app, which you would choose to install.