First row - service type ambient sound:
* No Service - silence
* 1x/E/GPRS - ocean
* 3G - birds
* 4G/LTE - buzzer

Second row - numeric signal strength dBm. Also each dot on the indicator adds 20% to volume for service type ambient sound. The app makes special tone indications when signal goes one dot up or down.

Third row - "ping" time. Response time in seconds for ping to Google DNS server 8.8.8.8. App tries to do a ping every second if there is no request in progress. Each successful "ping" is indicated by a beep sound. Also it makes a special buzz for first failed ping after successful one.