To use the mouse on two computers with Flow Multi-Device (i.e. the mouse automatically switches computers when the cursor reaches the side of the screen), Logitech software must be installed on both computers and both computers must be connected to the same wifi. However, the mouse has two bluetooth channels. You can therefore switch from one device to the other by clicking a button on the top of the mouse without having to install any software. This is less convenient, however, as the mouse sometimes doesn't connect very well at start-up, depending on the bluetooth receivers...

Under Mac OS, no software installation required. Via Bluetooth...