Winiff

Records Wi-Fi RSSI measurements.

When the phone is connected to a Wi-Fi network, this app samples the Wi-Fi RSSI measurements, made by the phone Wi-Fi device, at high frequency (~700 samples/second when tested in a Samsung Galaxy S7 Edge).

The app supports inducing artificial traffic between the smartphone and the Wi-Fi AP (it sends ICMP echo requests to the AP). This provides ample Wi-Fi frames to the phone to make up-to-date RSSI measurements (RSSI measurements are made by the Wi-Fi device only when new Wi-Fi frames are received).

Note, this app reads the Wi-Fi RSSI measurements from the "wireless extension for Linux" user interface; i.e by reading the pseudo file /proc/net/wireless. In some phones, the RSSI measurements are not reported to this file, and hence this app won't work in these cases.