RPN Calculator for Nokia N900, N810, N800 and N770


HP's RPN (Reverse Polish Notation) scientific calculators are just about the best one can ask from a calculator. This is the next best thing you can have without a real HP hardware.

Most (read almost all) of the work has been done by others, for more information about the original project see their site. I've made few hildonization things and a full screen skin so that it fits better on Nokia N900, Nokia N810, Nokia N800 and Nokia N770 device running on Maemo platform.

calculator image For N900 there is a new vertical skin in addition to the old horizontal one. Not all features of previous version are yet supported, like import/export of programs, printer and preference settings.

Vertical skin still looks odd in thumbnail application switcher view, other than that everything else should work.

N900 install (local copy)

Visit and download from maemo.org Free pages at http://maemo.org/downloads/product/Maemo5/free42 as an alternate place.

Other Nxxx models

For the other (non N900) models, there are some additions to original Free42, in particular

  • allows to switch to/from full screen mode using the hardware key,
  • has full screen skin for the pseudo HP-calculator 42c and
  • includes some quick-and-dirty Debian build files for the Maemo platform.

Only the decimal version will be built using these scripts as I think accuracy is much more important than speed. There are no other skins in the deb-package, but you may download more skins from original project site and drop them in /home/user/.free42 directory.

Copyright info

Hildon modifications Copyright (C) Tatu Männistö. Other copyright notices are in the source package.

All my modifications have been released under the terms of GNU General Public License version 2, see GPL for details.


Binary and source packages are available locally (see sidebar on left) as well as from Debian style repository at repository.tajuma.com.

There are also Maemo Garage pages for this port, see stuff in there.

Extra skins I have created are in this tar-ball.


Obviously people at Free42site, Sergio Melas for the initial hildonization and Bob Hauck for upstream 1.4.40 port and finger usage improvements.