From Nth Lab:
RPN is a programmable, postfix scientific calculator for the PalmOS: Programmable functions. Graphing - Solving. Macro recording. Many add-on scripts available. Drag and drop interface. 40 element wrap around stack. 10 user variables. Scientific functions. Base conversion. Number formatting. Graffiti or button based input. Copy/Paste. 18 digits of precision. Exponents up to +/-64000. Scientific, engineering, or fixed display. Programmable interface.
What's new in this version:
Palm OS 5 compatible (drawing bug fixed). Dragging beyond the end of the stack fixed. Deleting last script will now restore default scripts.