If you already carry a an iPad in your laptop bag, but use Windows or Linux on your laptop, you can use the iPad as an external monitor using: - a cheap HDMI USB capture device ($5 from Temu) - a short HDMI cable to connect that to your laptop's HDMI output - a USB to lightning or USB to type C adapter (depending on your iPad model) - a free app to display the UVC camera input full screen, e.g. https://apps.apple.com…
I've tried a couple of these and the quality is pretty shitty. Maybe they've improved since then.