When I got my first Palm PDA some ten years ago, I wanted to use it was a calculator. I was not satisfied with the rather limited built-in calculator program of my Palm V, so I decided to write my own. The result was PawCalc. Many years and multiple versions later, PawCalc 2.3 was ready.
PawCalc 2.3 is a powerful scientific and programmable calculator for Palm, and it includes everything from unit conversions and constants to complex numbers and fractions. And yes, it also does “normal” math. You can even add your own units and constants.
PawCalc is an expression-based calculator. This means that you type in expressions just like you would write them on paper. For example, if you want to calculate “32+2*5*sin 360″, then you just type that into PawCalc.
Here is what one user said in July 2008:
Your calculator is the best available today. [...] I continue to use an old Palm device simply to access your calculator. I have heard many engineer and scientist types comment on how useful you calculator is in practice. It is a terrific tool that stand uniquely between a calculator and a programing language such as MatLab.
As far as I have been able to determine yours is the only product of this type available where you can write an equation and then try different parameter values without having to rewrite the whole expression every time.
PawCalc is shareware. Read more about PawCalc at http://paweng.com/pawcalc.