I bought this app hoping to replace the rpn app Pcalc on my iPad dock - and it has done that successfully. The reason is that on my iPad I’m very often trying to use the calculator in a slide over or side by side with another app. This app does not hog the entire iPad screen when it’s the only app that’s open. So, with the iPad in landscape mode it does a really great job with split screen or slide over. Calculator widgets have functionality problems and this app doesn’t have a widget - no problem. The appearance is also very neat and clean, a very good looking design. I’ve had a bunch of different HP rpn calculators since the 1970’s, and now have no interest in apps that recreate those designs. The advanced functions of this app are quite good, sufficient for my needs and the conversion factor mode is really far beyond my need for a retired guy.There is only one major shortcoming - memory storage. I use that quite often with pCalc and any other calculator. I think that most people who are rpn addicts likely have that same need. Without memory storage it’s a bit troublesome. With it it would be a a five star app for its practicality.

Nice layout. Works well but needs one more thing. It is very necessary to have an x(exchange)y function on the keyboard. Many calculations need this capability to set up for a solution as RPN uses the x-y order for them....Please add this to an update if you can.

Had unbelievably awesome support from the developer. The app is packed with features that are so convenient to have right on my wrist, not to mention iPhone and iPad. Thanks for this app and true support.

Just as advertised - very clean, simple rpn calculator. It works perfectly, beautifully designed, no crashes. It has all the functions you are likely to need for scientific calculating. The unit conversion feature (actually, quite extensive) is a very nice extra. Suggestions for updates/improvements: have the calc float over the background wallpaper rather than having a completely white background, and ability to position to calc over the background and remember its position. This would be nice when iPad allows multitasking. A row of storage registers might be nice. Maybe showing more registers than the x and y registers is something to consider, but would probaby ruin the beautiful simplicity this calculator displays.