I love It July 2015

I put the date I purchased it here since I know there must be a lot of versions. I have tried every RPN calculator out there. I like this one the best. The horizontal is a perfect rendition of the classic calculator. In Vertical the choices were made perfectly. A reciprocal key and a square root key are the only functions. Both of these are handy for quick calculations I make in vertical mode. Also the keyboard area is not cluttered with ads or even settings. To change the FIX for digits you must go horizontal. The elegance and simplicity are ideal.

Fotohead about HP 15C Calculator