I made a short test, seems that the “signal strength bar indicator” is not updated after the mooshimeter was connected to the phone. I can walk through my apartment and the value is not changing.

Instead of the bars, you can use the “connection screen” which shows the RSSI value. The best value I can get is -24 dBm in one specific position (probably where the antennas of phone and mooshimeter are close together), when turning the phone at 180°, RSSI will jump to -40 dBm and less.