Congrats on the launch πππ! Super cool.
-Network throttling feature is great
-Rotate button is a good idea too
-"Mark as bug" is good because in startup development you'll get errors that nobody really cares about, so it's good that you let us decide what to mark as a bug :)
Some things I think could be better (take this with a grain of salt).
-It wasn't super obvious to me how to add multiple devices. My eyes were drawn to the left panel, and I thought that was how to add devices. But the left panel was how to replace devices. I think the button on the top right should be more apparent.
-On the phone (Galaxy Note 9), when I set zoom to 150% it brings the whole device closer (which is what I want). But on desktop, it just zooms in from the device's perspective and doesn't bring the whole device closer. Is that intentional?