When I had a Palm III I used extensively LispMe, a Scheme development environment for Palm OS. It was quite capable, supported GUI primitives, and I had lots of fun writing several programs including a bytecode disassembler.
In this paper the developer described the implementation and architecture of LispMe, which did a lot with the limited resources of the device:
@francina1909 se nel pacchetto includiamo anche i nostrani Meloni, Salvini & C. sarebbe decisamente meglio. Non mi chiamo Rowenta e quindi non sono uno che si accontenta... Buon San Silvestro e buon 2026 Francy 😘