This appears to be a simple device that helps people with reduced motor skills to hold a pencil and use it to write. There are several low-tech devices on the market that serve the same purpose, but this one seemed unique in the way that you do not have to be able to hold the pencil itself. Instead, you can hold onto the larger grip of the product.
This is a pretty familiar adaptive technology. This button is used at many public doorways. It sits at the level of someone who is using a wheelchair, and it can be used to open the doors automatically. Additionally, after it is pushed, the doors will remain open for some time. However, I am not sure if the amount of the time the doors are open varies or if this is even enough time in most cases for people who have varied disabilities to be able to enter or exit.
This is a fixed seat for rowers who might not be able to move their whole body forward and back. It remains in one position, and the rower can keep their spine constant while rowing. However, clearly, the seat belt feature seems like it could be very dangerous if the boat were to tip.
Great array of technologies! Please add (or at least remember for next time) to link to where you found this information.
As to your on-point safety concern about the fixed seats: the seat belts are designed for fast release in the case of tipping; the boats with fixed seats also use pontoons to greatly reduce the probability of tipping.