First of all, nothing beats 12Calc. There is no substitute unless you are using a real 12C, but then 12Calc has all the speed of your iPhone. The latest version, however, is problematic as the font is now white instead of black. Depending on your situation it can be very hard to see. I wish I did not upgrade so I could have kept the previous color scheme of black numbers on a lighter background. Update: Years later this app has been maintained and still works wonderfully. Thank you!

Ernest Brock has done a phenomenal job with this App. I first downloaded a version of this years ago when it was offered free for a short time. Then (I believe) HP asked Ernie to make some changes. I was extremely worried when I updated my first iPhone, because I thought I would lose this App. But it kept on working. Finally with my iPhone 7, I finally broke down to repurchase the newer (and improved) version. If you are a fan of HP-12C calculator, then you will likely find this App very intuitive, and I won’t go into describing all the ways it can be used. But some of the novel features include: * Currency converter, and current currency values can be updated whenever you want. *. A “tape” feature, so that you can see what an adding machine tape would show if it were part of the HP-12C calculator. And although I don’t use it for much more than a basic calculator with financial and real estate (loan, mortgage, PV, etc) calculations as I did for years with my regular HP-12C, I can honestly say that I use this App ALL THE TIME, especially during tax season! Finally, over the years I have had 2-3 emails with Mr Brock, who has always been prompt, honest, and provided me with valuable tips and help. Just what you want with a developer. So, stop reading, and go buy the App! You will find it very worthwhile1 2020 is here and my earlier review still stands. Great App. Great support. Go get it!

If you are a fan of the old HP12 with RPN this is well worth the purchase. I use it on my iPhone and iPad and often comes in handy. . . Usually when I least expect it! Thanks

Works well

I have been an HP-12 user since forever. This app emulates all the features in the original hardware unit while adding many additional functions including a host of conversions. I use almost daily and find it to be always stable, accurate and reliable, while surprising me every now and then with a new feature I discover. THIS is why we buy smartphones- everything you need, always at your side. Fabulous implementation of a wonderful product, only improved. Wonderful accomplishment!!!

Better than the HP12c and the updates keep it current.

The app works well. The additional function of seeing the tape is very useful. Worth the investment.

The HP 12C, with modernized keyboard, a multitude of built in templates, and unrivaled accuracy of calculations, currency conversion immediate updates, and many useful templates.

Great App!

I’ve been using this calculator since it first came out on the Palm Pilot. It has since evolved and has a digital tape as well as a very handy conversion function for every day use including currencies and imperial to metric. Just buy it, you’ll love it.