For people who sit in a wheelchair for the duration of the day they often have a lap tray that can be installed on their chair to be able to easily eat, read, etc. Most tablets are mounted on gooseneck arm devices attached to a wheelchair and are awkward to set up for best use and to reach easily. However, having a tablet permanently set up and taking space on a wheelchair tray makes its use for other purposes difficult.
Your task would be to develop a system to have a tablet held underneath a wheelchair tray on a hinged element so that the surface of the tablet holder would be fully level with the tray. Then the portion with the tablet would be raised to expose the tablet and set it at a proper angle and height for use. Ideally this activation of tablet raising and lowering would be done remotely on either a power or manual wheelchair. It must also be made of a material that is easy to clean and avoid staining.

Here is an example of a wheelchair tray:
https://www.walmart.ca/en/ip/Wheelchair-Lap-Tray-Gray-Wheelchair-Tray-Table-Accessories-with-2-Cup-Holder-Medical-Portable-Wheelchair-Desk-Accessories-for-Eating-Reading-Resting/PRD6UOVAO3NLWKI