RealCalc can't set to RPN mode

[Kevin the Drummer]

I have a Droid Razr Maxx and downloaded the free version of the RealCalc Scientific Calculator Quartic Software It did NOT default to RPN mode, and a web search told me that I could enable RPN mode through the setup dialog in my phone. I didn't find any mechanism to do this, nor did I find help in the FAQ for that.

How can I coerce RealCalc to go into RPN mode? It looks like a fantastic calculator, but RPN is an absolute must have for me.

Thanks much people....