Open calculator, then pull out s pen, either a note will pop up or just press the s pen button and double tap.
Now you can move the s note around while using the calculator and alternate between each.
I am on android version 4.1 and I don't think that will enable the multiscreen with s note and the calculator as you requested.

 

I just played around with this. Only S-Note appears in the multi-window bar. It seems the only way to do it easily is with popup note as you said. Using the full screen S-note means you have to use the home button to switch between apps.

 

Not really the greatest looking calculator and not many settings available, but for what you were asking to do, I think it'd serve its purpose:

https://play.google.com/store/apps/...GwsMSwxLDEsImNvbS5ta2lpc29mdC5wb3B1cGNhbGMiXQ..

 

S-Note will work in multi-view, the calculator isn't configured to work in multi-view. If you didn't mind moving the bar, separating the programs, up or down and have access to all apps in multi-view you can make it work to a degree.

 

I use AirCalc.

 

Thanks! This app is awesome on the Note II. :rock:

 

It sure looks better but it doesn't have the memory feature. If it did I think it would be perfect.

 

Thats cool it even has the memory feature just wish it looked better.

Opps! It doesn't seem to work right when I do 6x3= it gives 6.0 and that is all. Well it does work but but not the way I am used to one working. I think it would be called a financial calculator. Because when you type 6*3 it expects you to continue with more functions like another multiplication or addition instead getting your answer by hitting equal. Looks like air calc is better for me.