There are lots of folding keyboards available. The problem is that they are made for using on a table. Phone doesn't work well on table. It should be possible

There are lots of folding keyboards available. The problem is that they are made for using on a table. Phone doesn't work well on table. It should be possible to make keyboard the size of a phone that can be used in the hands. The problem is how to hold it, maybe the iPhone magnets would make that possible. I think the main problem is that everyone is used to using touchscreen keyboard and wouldn't think to use keyboard. I have an ancient Stowaway Bluetooth keyboard, one of the best folding keyboards made, and I have stopped bringing it along. I found that screen keyboard is fine for small amount of typing. And if I need to do actual work, then laptop or tablet is needed.