iPhone or Apple Watch as an external keyboard for an iPad I'm interested in using a 3rd party app (GoodNotes) for a presentation on my iPad. When a keyboard is connected to the iPad, clicking the right arrow will advance to the next page/slide. However, I do not want to carry a full bluetooth keyboard while presenting.

Is there any way to emulate a bluetooth keyboard from my Apple Watch or iPhone such that I can control the iPad? Or, is there another way to control the iPad with an AppleWatch or iPhone?

I've found one possible solution called WeBe++, but I would like to do this without jailbreaking the iPhone.

I realize that many keyboard and mouse emulation apps are available, but these require a host application to be installed and therefore do not work on the iPad. They do work well between an iOS device and a Mac.

In case no solution to the above is available, I would consider other solutions that combine the AppleWatch and iPad, or iPhone and iPad. I also looked at PowerPoint and the WatchOS app, but it requires the iPhone to be the presenting device. I will need to the ability to draw on the iPad during the presentation with an Apple Pencil and I would like to save the notes after the presentation.
In order to make an iPhone appear as a Bluetooth keyboard/mouse/HID you need to jailbreak it. It is not possible to an iPhone as a keyboard as of today running iOS 11.0.x.