Service quality icon with exclamation mark

Because the cell signal is strong doesn't mean the data connection is also strong. The app  indicator shows the latency between the device and the server with this legend.

5 bars -- less than 250 ms

4 bars -- 250 .. 500 ms

3 bars -- 500 .. 1000 ms

2 bars -- 1 .. 2s

1 bar -- 2.. 4s

/!\ -- 4s or more latency, or temporarily loss of connection