Free42

Works great and no ads! For a fast intro to usage google HP-42S manual.

Helt konge. Endelig en tekniksk HP kalkulator som er og ser ut som originalen. Love it. Hilsen hp-kalkulator bruker siden 1973 (hp45)

I appreciate your effort to make and maintain this app. I've probably used it since it came and still use it as my ever favorite and only calculator. It works exactly as expected. Thank you!

Some changes seem to be made in the app recently. It gives error messages: "Not a number". A good app has been unusable ( I've been using a real RPN HP since 1978...)

Not sure why, but the square root function doesn’t seem to be working properly now. Was working okay before. Not sure if other functions are also impacted. Used to love this up until this happened

I have always used HP RPN calculators spanning a period of over fifty years and this App is a faultless rendition of the original calculator. One really niggling problem is that the screen has rotated 90 degrees to landscape. Trying to get it back to portrate does not work. Any ideas? Any fix coming? Ray Shead

I’ve been using my hp42 since buying it the day it was in stock for sale. Its a one-owner! On back it says 1987 Made in USA. SERIAL No …A11141. I digress. Some of my keys have started to act up after 36 years of perfect service. Finding Free42 is a godsend! I’m running it on an iPhone SE. I re-entered some really old programs I’ve kept on my 42s and they work flawlessly. I am so grateful you’ve created this app. Thank you, thank you!

I’ve been a fan of RPN for over 40 years. This calculator works great. I don’t typically use it for much more than simple calculations but I use it daily. I absolutely love the haptic feedback with key presses. It’s gives great indication when you’ve typed a number.

Terrific!

Terrific, but will get 5 stars when it has the shake to clear stack that 42S had. But this app is 64 bit and 42S is out of the app store. Any chance of getting this great feature?