Visionary App - RPN on Steroids – ND0 RPN Graphing Calculator Review

I wrote the following review for the ND1, but it is equally applicable to the NDO: In one of several default/static modes, the latest release of ND1/ND0 (1.5) is arguably the best RPN calculator app available on any mobile platform. (Trust me, I know. I have owned HP/RPN calculators since my HP-45 decorated my belt in High School. Don't tell my kid's friends. . .) Out of the box, the ND1/ND0 provides a significant subset of the functionality of the HP 48/50 class calculators. But rather than being just another emulator, fixated on replicating the "classics" and repeating the past, the ND1/ND0 pushes forward. It is as much of a calculator development platform as a calculator. It is extremely configurable. Not only can one reconfigure the keyboard and it's keys, but one can affix one own's code to any key. Moreover, this can be done in native RPL+, in JavaScript or in combination. As a result, the ND1/ND0 is able to work with a wide variety of classes, including the traditional numeric classes, but also BigInts, Rationals, Complex, Colors and Images. (Classes, as well as other customizations, can easily be created by the user and shared with the broader ND1/ND0 community.) Here-to-fore, my favorite RPN iPhone app has been the HP 42s (which I rate 4 *'s). Though it's an amazing replica of the original, the project is focused on recreating the 42s, as opposed to pushing forward. Though superbly engineered, it was done at a time when dynamic reconfigurability of the keyboard/functionality was limited. In contrast, the ND1/ND 0 is easily reconfigured. Currently, I am taking a Chemistry course, so I wanted a 42s type calculator that has physical constants built-in. I was easily able to reconfigure the ND1/ND0 to do so. Moreover, for my day job, I wanted to include a core-set of financial functions, which I was also able to easily add. As impressed as I am with ND1/ND0 in its current incarnation, I believe the best is yet to come. I believe that the developers of ND1/ND0 will continue to focus on configurability and expandability. Lest you feel intimidated by all of the power of the ND1/ND0, don't be. As I mentioned, it is ready to go right out of the box, but it's nice to know if one wants to make "tweaks" that these can be easily accomplished.
Review by Coollinrhrhrgrg on ND0 RPN Graphing Calculator.