Bluetooth Keyboards definitely bring a lot of great benefits to today's iPads, making it far easier to type and control apps. Things are no different when it comes to using Switcher Studio in conjunction with a Bluetooth Keyboard.
Once you have successfully connected your Bluetooth Keyboard to your iPad. Launch Switcher Studio.
Set up your cameras as normal inside Switcher Studio. You will notice that the cameras are all labeled 1, 2, 3, 4, etc. This is important.
Your Bluetooth Keyboard should have number keys at the top of the keypad. All you will have to is tap on 1-2-3-4-5-6-7-8-9 in order to switch which camera is shown in the Preview window.
After this, you can adjust the camera in the preview window as normal and hit "Preview->Live" to go Live.