Did you hear anything about HP41C RPN calculators?
The HP-41 series are programmable, expandable, handheld RPN calculators made by Hewlett-Packard from 1979 to 1990. The original model, HP-41C, was the first of its kind to offer alphanumeric display capabilities. Later came the HP-41CV and HP-41CX, offering more memory and functionality…
If you addicted to your HP41C (Like me!) you can purchase it again from AppStore!!
AlSoftware released a HP41CX+ (named i41CX+) emulator for iPhone.
Today I install it on my iPhone 2G, It’s working fine! First thing that I try to use is the beep function “… Press shift then press 4…” But the results is a noise! instead of 41C’s clear sound 
! Then I try to do something with programing function it’s as good as the original 41C programing (also a bit better when using iPhone keyboard instead of 41C’s alpha function)…! I
t also supports expansion Modules and Overlays!!
Disadvantages:
- Very bad beep sound!
- Multi-Touch not supported! (Hold Clx then Turn on 41C, result is nothing instead of resetting memory!)
- Printer’s key located in bad position (Upside Left & Right)
Read more about HP41-Series:
