Reminded me of the tool turning Pocketbook E-Ink readers into computer monitors, which I made several years ago:

https://github.com/borzunov/remoteink

This could also be used for the dashboards if connected to a remote server or a Raspberry Pi (no screen updates happen if the content doesn't change).

Besides that, it allows to zoom in/out, switch between the opened windows, and move around the screen with keyboard shortcuts. No jailbreak is needed for the reader.