HP Prime Pro

I've been a long time fan of HP calculators. Love having a full powered HP calculator on my desktop. I wish the text was resampled and re-aliased in the emulator, and I wish the app's window size was more adjustable, but all in all, great calculator.

No it's not free, but it is worth the $20. All the other calculator apps on the windows store are just a joke. This has all the functions of a standard graphing calculator, and then some. If you are serious about school or math, then you should have this in your arsenal. This is a steal compared to a physical graphing calculator which needs batteries and can get damaged / lost.

On my HP laptop if I enter a number then press the subtract key on the numeric keypad the sign of the previous entry is toggled. Pressing the key multiple signs continues to toggle the entry sign from plus to minus, etc. If I press the minus key on the alpha numeric portion of the keyboard I get what one would expect, i.e., a minus sign after the first number entered, indicating the next value is to be subtracted from its predecessor. This may be by design to facilitate entering a negative number. If so, it would be good to have it pointed out in the documentation so as to reduce errors. I seems as though the - key on the numeric keypad has been mapped to the +/- key on the calculators virtual keyboard. After about 10 days of use and the 2/15/2017 upgrade I am changing my rating to 5 stars. Great app. Had to reset; which wiped out all my functions; as the crashing kept getting worse. Better now but not back to normal. Program has started exiting when certain buttons are pressed.