HP 12C Platinum Calculator +4

Hewlett Packard has a loyal following and a reputation for highest quality - and for correcting problems when they arise. (Early HP scientific calculators actually were recalled and replaced when a tiny bug was discovered.) But a business calculator that makes elementary-school math errors (e.g., in squaring a negative number) is unforgiveable!

The calculator on which this app is based goes back to 1981, and among financial wizards both old and young, it is still the gold (well, platinum) standard! This iPhone version appears to have been introduced in 2009, which should have allowed HP plenty of time to get it working credibly under OS 3.1 or later.

As of October 21, 2017 this app works great in iOS 11. Given that HP is now using a cheap low cost provider to make the new physical calculators out of Asia, this app is the only HP12c worth buying. The new physical calculators don’t register half the keys if you type fast. This app is great for iPhones and iPads. Make sure you get the platinum version in order to have the latest features such as backspace.

This specific developer has not been able to update this App to function within the last 4 years of iOS updates. Prior to that it worked great, just like my actual HP 12-c. During the last 5 years approximately I have reinstalled the updated versions and they ALL crash during financial calculations ALWAYS. Today I tried again and still crashes. Developer needs to take this App down or get it working. This is not a rare issue.