The tool is called OSWarp. It gives you a simple shortcut and a friendly GUI to reboot into the other OS. With this tool, no need to wait for the GRUB menu anymore. Just a simple click. If you only have Windows and Linux, it can select the right item for you. Please give it a try and tell me if there is anything I could improve.
After a whole month working with AI, I was finally able to root this device and do this. Once it was done, it just works so well. This device has a fully functional Wacom pen with pressure and hover support. It's a shame they only limit it to their official apps.
(And they patched the ADB exploit I found btw. I don't really care since I disabled the software update anyway.)
It can install apps by default. But since I don't want to send my data to their server. After getting full ADB, I debloated this device, removing most of the original apps. Replaced the launcher with inkOS, installing KOReader, etc. I posted a tutorial on XDA, you can search for that if you need. I'm planning to develop some e-ink-specific apps on this device.
I also made some minor improvements to it. This device doesn't have a physical back button. Therefore, the way they provided to go back is by showing a floating menu above any app. I thought that's very dumb. So I modified the inkOS launcher to utilize the "AI button" at the top as a back button. And it works quite well.
I don't really recommend this device if you are purchasing it mainly for the AI or the note part. Since you need an account to literally do anything, even to export your own on-device note to PDF. Since I just want a 10-inch tablet that looks slick, it's good enough for me.