# 11C Scientific Calculator — user reviews > 164 indexed App Store user reviews of 11C Scientific Calculator by Vicinno Soft LLC, rated 4.20/5 from 298 ratings. - Source: https://appshunter.io/ios/app/11c-scientific-calculator/id530593018/reviews - App overview in markdown: https://appshunter.io/ios/app/11c-scientific-calculator/id530593018.md - Rating breakdown: 5★ 211 · 4★ 31 · 3★ 9 · 2★ 7 · 1★ 40 ## What do users think of 11C Scientific Calculator? Overall sentiment: positive **Pros** - 🚀 Excellent emulation of original HP 11C calculator - 👍 Familiar and intuitive RPN interface - 🚀 Convenient to have calculator on phone - 💡 Ability to program and save calculations **Cons** - 🐛 Occasional crashes or unresponsiveness with iOS updates - 🔍 Small display size on some devices - 🔍 Manual access issues **Commonly reported bugs** - Blank/white screen issues - Compatibility problems with newer iOS versions **Most requested features** - Ability to adjust font size or display layout - Support for additional languages/markets ## Newest reviews (18 of 164) ### 5/5 — Genial *2023-02-28* Ich freue mich sehr meinen alten Taschenrechner wieder gefunden zu haben. ### 5/5 — Vicinno 11C SciCalc *2023-02-12, version 1.73* An excellent clone of HP11C, which is a superb, uncluttered scientific RPN calculator with modest programming capability. Indispensable everyday working tool for technocrats of all stripes. Highly recommended. ### 4/5 — Just downloaded app. So far, so good. *2023-01-30, version 1.73* I still have, and occasionally use, the HP11C I bought in 1986. I’m very glad to have this app on my iPhone 12 with iOS 16.1.1. The “click” on every keystroke is a good substitute for the old HP11C “feel”. ### 5/5 — Schonung des Originals *2022-09-18* vielen, vielen Dank — Dank der App kann ich das Original in der Schublade lassen und ab und zu Interessierten zeigen. Man sollte aber einen der Rechner kennen, damit man sich die wunderbare Tastatur vorstellen kann. ### 5/5 — I Like It *2022-08-28, version 1.73* I purchased my first 11C probably around 1976 or so on the recommendation of my engineering student brother who explained the advantages of RPN to me. The transition was easy since I was not a calculator user prior to its acquisition. I have three now, one at home, work, and on my boat. I have been a machinist for 35 years so the one at work sees the lions share of use. I am absolutely thrilled to now have it on my phone so I have instant access to it 24/7 regardless of my location. The majority of my use is simple number crunching and trig functions so I could not be considered a power user or expert on it but I am absolutely happy and satisfied with this app on my phone. Now when at work if I am standing in front of a machine tool and want to add or subtract two numbers I whip out my phone rather than walk the 30 or 40 feet to my office and back. I am highly protective of my beloved 11C so it rarely makes an appearance on the shop floor for fear of being damaged or destroyed. ### 5/5 — Phenomenal Calculator! *2022-06-13, version 1.73* Easy to use if one if familiar with RPN or HP Calculators! A must have! ### 4/5 — Manual Access Is Corrupt *2022-05-31, version 1.73* Great except that the manual does not work. You only get the first few pages. The others do not appear. ### 5/5 — Wonderful RPN format calculator *2021-12-24, version 1.73* This calculator works well on my iPhone. The RPN format is great and I use it in my laboratory and at home. ### 5/5 — HP 11C *2021-11-01, version 1.73* Great product. Works just like my old HP. thanks for sharing it. There have been many times that it has been very handy. Thanks ### 5/5 — Hp11c great engr Calc *2021-10-11, version 1.73* I Have used the HP 11 C calculator since I was in college. I really enjoy simplicity and accuracy. This iPhone version excellent seems to be same as my calculator and always available because it’s an app. I love it and use it a lot! ### 5/5 — Love it, lovage a part of my brain *2021-06-19, version 1.73* Got my HP-11C in 1984. Immediate hooked into my brain, Matrix-wise. I just kinda naturally think in Reverse Polish anyway. It lasted thirty freaking years! This app gets the closest to the HP-11C’s look & feel of any I’ve seen. ### 4/5 — Stopped working in iOS 13. Working again :-) *2021-02-19, version 1.73* Like the app. Used it a lot. No longer works after updating to iOS 13.2.3 Update: tried launching again in iOS 14.x and it’s working again. Happy again! ### 5/5 — Bill - Engineering Tech. *2021-01-14, version 1.73* I bought the calculator first when they came out in the 1980’s(??) and still use it in my work. Then I downloaded the app and it is equally great. With an IOS upgrade, it stopped working for a little while until it was updated to the newer IOS. I recommend it to those who are scientifically minded and like RPN. ### 5/5 — HP 11C *2020-12-17, version 1.73* Reverse Polish calculators are the best. ### 5/5 — Old school cool *2020-12-14, version 1.73* Love it, simulates my real HP perfectly. Long live RPN! ### 5/5 — The Way Nature Intended *2020-10-24, version 1.73* Since I bought my first HP-11C in 1985 and exposed to RPN I never looked back. I have never found a better calculator. Period. Stop. Now that I have it in my phone, I’m complete...no more hacking at some poor excuse for a calculator! ### 5/5 — Best calculator and app *2020-09-03, version 1.73* I have loved my (real) HP11C for almost 40 years. This app re-creates it perfectly. ### 5/5 — Top ! *2020-08-28* Du bonheur de retrouver ma calculette d’élève ingénieur .... ## Most critical reviews (10 lowest-rated) ### 1/5 — App doesn’t work *2025-06-09, version 1.73* Just downloaded the app, it doesn’t work. Whenever I open the app the screen is a blank white page. Hopefully the developer can provide some assistance. ### 1/5 — Blank, White Screen *2024-08-18, version 1.73* I went to the menu to turn on auto rotate and when I tried to go back - Blank, White Screen Now I'm out 6 bucks - ripoff ### 1/5 — Still won’t open! Return my money!!! *2020-05-10, version 1.73* I bought this app many years ago after my great HP11C finally failed. Loved the app! Gave it a great 5-star review, and I normally do not review apps. Just like the 11C without needing to carry an extra device around. But months ago it would no longer open. Eventually, I gave up and deleted it. I saw in the App Store that it was available again, checked recent reviews that indicated the non-opening issue had apparently been fixed, and paid for it again. It will not open. I’m running iOS 13.4.1. Useless waste of money. I thought the problem had been fixed. Please fix it or return my money. I’d rather you fixed it; it’s well worth the money if it works! ### 1/5 — Does not work with iOS 13.3.1 *2020-03-30, version 1.63* This does not open at all with latest os system On my iPhone 6s Plus. Apparently they are not updating the app. ### 1/5 — App Crashs immeditally *2020-03-16* The App does not start ### 1/5 — No working with iOS 13.3.1 *2020-03-02, version 1.63* No working with iOS 13.3.1 ### 1/5 — Não abre no IPhone X *2020-02-18* Decepção. ### 1/5 — No longer works... *2020-02-09, version 1.63* This was one of the best HP 11C emulators for the iPhone, but this app no longer works since the IOS 13 upgrade. Looks like it has not been updated since 4 years ago. So sad! ### 1/5 — Doesn’t work with iOS13 *2020-02-06, version 1.63* This app needs to be updated to work with iOS13. It just crashes every time I try to open it. ### 1/5 — May not matter now *2020-02-05, version 1.63* My favorite calculator app (11C Scientific Calculator) no longer works in iOS 13. Trying to go to vicinno.com results in a big nothing. In you folks are still there and in business, please fix this. ## Most praised reviews (10 highest-rated) ### 5/5 — Like a Dream *2026-03-17, version 1.73* This simulation feels exactly like my 11C I bought in 1985 and that got me though Fluid Dynamics after going through 2 T_s. Love the 11C more than any I’ve ever used. It still works perfectly but with mobile phones who carries a calculator any more? It’s such a pleasure to be able to do my calculations on this phone. ### 5/5 — Old Dependable *2026-03-17, version 1.73* All the convenience of my familiar old calculator, that I’ve used since high school, without having to carry it anymore. After 40 years of trouble free operation the old HP deserves retirement. Emulator App works perfect on my iPhone ### 5/5 — RPN is best *2025-05-19, version 1.73* Yes ### 5/5 — Wonderful *2025-02-28, version 1.73* I’ve used the 11 C all my professional life. I was delighted to find the emulator so I don’t have to lug the actual calculator around. Thank you so much for providing this great tool. ### 5/5 — Patrick *2025-01-31, version 1.73* Great app. I’ve used an 11C since the late 70’s and still use my original. I guess they made them too good. This app allows me to use it whenever I have my phone ### 5/5 — I think in reverse Polish notation *2024-06-26, version 1.73* What’s not to like? ### 5/5 — Coole App 😎👍🏽 *2024-06-17* Funktioniert wie das Original, das mir fast 40 Jahre treue Dienste geleistet hat. Schön gemacht! ### 5/5 — i love this app *2024-03-12, version 1.73* I purchased this HP 15C calculator app becauee I've used the original HP 11C, since 26th September 1986. It is fun to use on my iPad. ### 5/5 — HP 11c Calculator *2024-01-19, version 1.73* Best scientific and engineering calculator ever made. ### 5/5 — very happy to get a New HP11c ! *2023-08-27, version 1.73* My 1981 is still working like new, but sure doesn’t look it. This app makes my iPhone and iPadmini just as good as the real thing. For several weeks I did all kinds of stuff on it to see if it had any flaws/errors. Zero !!! and I love it as much as my original. One minor annoyance; when I hit prefix to see all digits, it just flashes the digits too fast for me to read. My old HP showed it as long as I held the button. But still a 5+++ Thanks for the exceptional re-creation. --- *Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-09-10.*