Max of BLE devices simultaneously detected by a Smartphone in Central mode

I  would like to know how to compute or optimize the maximum number of BLE device (in advertisement mode) that can be detected by a Scanner (Smartphone app).

I can not find any answer of the maximum number of devices detected in the "same time" ? is it 10, 30, 100 or more ?

- Which parameters can be customized on the peripheral side to detect maximum number of devices ?

- Is it possible on the peripheral side to know if the device has been detected and stop the advertising during a period ?

Stoping the advertising will liberate some bandwidth for other devices ...