# GO-25 SciRPN — user reviews > 39 indexed App Store user reviews of GO by Steve Lidie, rated 4.70/5 from 23 ratings. - Source: https://appshunter.io/ios/app/go-25-scirpn/id408249517/reviews - App overview in markdown: https://appshunter.io/ios/app/go-25-scirpn/id408249517.md - Rating breakdown: 5★ 20 · 4★ 2 · 3★ 0 · 2★ 0 · 1★ 1 ## Newest reviews (16 of 39) ### 5/5 — Fantastic *2015-12-08* Couldn't be better except limiting memory and speed to the original specs for added nostalgic effect. ### 5/5 — This one is good *2015-10-24, version 2.4.21* This is less photorealistic than some others but I really like it because the HP-25 was what I wanted as a teenager (but couldn't afford) and it has a good balance of functions and as an app it seems to work well (within my relatively simple uses). Thanks for creating this. ### 5/5 — Amazing Rendition *2015-05-28* When the on-off switch on my 25C gave out I got a 32SII. For those that had a 25C, the faithfulness of this rendition is amazing. I prefer the 25C emulation to a 42S emulation because it is more Spartan. For those that want more keys to fat-finger (37 instead of 30 is noticeably more crowded) and more programmability (why when for anything serious you have something like Mathematica?) there are at least two emulations of the 42S on the App Store. Nits: The tiny green LEDs, the blue info button, and the fact that the iPhone's status bar are not hidden all distract from the purity of the experience. How about an super-retro mode where all those are gone? A more evocative app icon? Maybe just 0.00 in red LEDs? I didn't find either of the keystroke sounds satisfying so I had to turn sounds off. The 25C had a padded yet definite click that I guess is hard to duplicate. Needs some finger grime and a flaky on/off switch to be like I remember. ### 5/5 — Very very good job *2015-04-23* The implementation of the old HP 25 is exceptional. Perfect for a trip back in time. ### 5/5 — Retrouver ma vieille HP25 *2015-02-19* Franchement que du bonheur de retrouver cette calculatrice. Et mes réflexes de notation polonaise inverse. Merci ### 5/5 — Pres *2014-12-24* Installed the latest update and the app no longer runs. The calculator screen appears then disappears. Running iOS 6.1.3. Disappointing. ### 5/5 — What happened ?? *2014-12-18, version 2.4* As of 18 Dec/ the Go-25 app replicating the HP-25C, not longer functions on my iPod Touch, OS 10.6.6 It needs to be corrected ASAP. ### 5/5 — Beautiful App! *2014-12-15* Feels and works exactly the same as almost 40 years old original! Superb support service! Steve, you made my day! ### 5/5 — Greatest calculator ever *2014-11-16* This was the greatest app until OS8.1, now it does not work. When it gets fixed, definitely buy this one. ### 5/5 — Outstanding HP 25 emulator *2014-10-31* As a college student in 1975 I spent the entire summer works wages on the original HP 25! I STILL have it in perfect working condition and its a cherished treasure. Now I can have its functionality with me all the time on my iPhone 6! Once you've used RPN you NEVER want to go back! Thank you!!!! Bo ### 5/5 — Old Surveyor *2014-10-04, version 2.2* I used one of these all through college and took my LSIT with one and all I can say it what a great retro app. Still use it for quick surveying calculations! Update IOS8, Since updating to 8 the register and stack graphic disappeared and thecalc keyboard is clipped at the bottom. Love this app Update: My bad the app is working perfectly, no problems! ### 5/5 — A welcome blast from the past *2014-03-08* It was December 1975 when I bought my very first HP calculator, an HP-25, at the Harvard Coop for US$199, a cost about US$1,000 in 2014 dollars. It was a great product which got me hooked on RPN. When I saw this app, I bought it for the awake of nostalgia and also as a tool. Let me say that it is totally faithful to the original, except that the original had only 49 (not 99) program steps and lost all memory contents when switched off. Strongly recommended from an old timer who has seen the rest and knows the best. ### 5/5 — Better than the original *2013-12-16* I still use my HP-25 as my "daily driver" calculator, and I can't use anything else but RPN. GO-25 is a spot-on emulation of the original. The graphics are gorgeous; the buttons are shaded and highlighted very attractively. ### 5/5 — My HP-25 has come back to life - JOY JOY JOY! *2013-09-15* This app is SO FANTASTIC - it is a gorgeously accurate visual and technically complete implementation of the HP-25 RPM calculator. The new Version 2.0 brings even more snazziness to the picture. My HP-25 died long ago - but this app has brought it back to life for me and, to this day, I love how it does so many cool things. Personally, I learned a lot about programming with my original unit and RPN was just a part of it. There are calculators - and there is the GO-25 - it works great and looks fantastic. ### 5/5 — Very nice recreation of the all-time classic calculator *2013-01-25* Extremely realistic looking, easy to use (even better on the iPad) and working exactly like the original! And there is more: Stack and register display, program editor, export/import programs and more... 100% recommended for all HP enthusiasts. ### 5/5 — HP-25C Programmable Calculator *2012-12-09, version 1.7* Absolutely spot on! I bought in college, and still own, an HP-25c Calculator that operates to this day. Now I have the equivalent on my iPad! Fantastic job! Love it! ## Most critical reviews (10 lowest-rated) ### 2/5 — Huh - looks like a phone app *2026-05-15, version 5.1* This looks like something that was created for the iPhone and just ported without any consideration for screen size - I’d like to see this 2-4 times its size if I’m on a desktop ### 3/5 — Great - I love it … but how to get out of the paper trail? *2024-03-17* I love it … my first calculator was an HP-25; now I can still use it on my phone and iPad … nothing better than that. But every now and then, I do something such that the paper trail pops up. (That never happened on the real thing …). Now - I still haven’t figured out, how to close that paper trail again. Every time, I’ve to kill the application and restart. Why can there not be a simple ‘x’ to close it? That would bump my rating to 5-star. ——- Thx for your reply; I didn’t need read much of the manual to understand my original HP-25; but I agree, I’m old and times change … - disappointed. Just let me disable these paper trails! Make it a pro version on this feature alone and I pay you $10 **Developer response:** Full details in the App’s documentation, section Gesture Summary. In short: Double tap the calculator display to show/hide the stack, memory and paper tape views in RUN mode. Double tap the calculator display to show/hide the program description and listing views in PRGM mode. Thanks ### 4/5 — Slow button response resolved *2021-03-30* Deleted app and reinstalled on my iPhone 6s. Working well now. btw very happy to have the calculator I used in college on my phone! **Developer response:** Good to hear all is well. I am unable to see the problem on a virtual iPhone 6s, nor on an actual, still working, iPhone 5. Please send email to support if the problem arises again. ### 4/5 — HP 25 Emulator Key Clicks... *2015-01-16* Everything is great except there seems to be a noticeable delay between key presses and the digit entering that becomes somewhat annoying. i41cx emulator is instantaneous on key presses. However, if you went to university engineering and math courses in the 70's the HP25 is still the HP of choice... The 41 is almost cluttered onscreen because of more keys. The 12c isn't at all for Engineering Types. The 25 is Just Right. Hope you can tighten up the speed on key clicks. Beautiful App. ### 5/5 — Faithful *2025-10-13, version 5.1* I used a HP25c in 1970’s. This is a very faithful emulation that I’ve used for many years. ### 5/5 — The best HP25c *2024-12-23* The best HP25c emulator I could find. ### 5/5 — My favourite calculator. *2024-05-27, version 5.0* I have this on my iPhone. I purchased a HP-25 in 1978 and used it through the final year of school, through university and into my teaching career. I only stopped using it when the battery pack died then I discovered this app. Bliss! Once you learn RPN you can never go back. I love this app - it is identical to the real thing. My only bugbear is "How do I turn off the Stack/registry screen?" I just seem to randomly tap the screen for minutes until it randomly turns off. There must be an easier way. Help. ### 5/5 — Great app! *2024-04-29* This is a wonderful app. Completely replicates the HP 25 RPN scientific calculator with full fidelity. ### 5/5 — Probleme mit iOS Version 9 *2020-03-09* Leider diese neue Version läuft nicht mehr an meinem iPad mit iOS Version 9!!! Wie kann ich wieder die alte Version installieren? **Developer response:** Please turn off iCloud storage. Go to iOS Settings / GO-25. iOS 9 iCloud support cannot be supported. ### 5/5 — Old HP-25 user *2019-03-25* I’m very impressed with this program. With the latest update I’m starting to like this app as much as the original calculator. If only the keyboard was the same... ## Most praised reviews (4 highest-rated) ### 5/5 — I wish I’d found it sooner! *2018-09-08* This is a wonderful simulation and has become the go-to calculator on both my iPhone and iPad. If I had found it years ago I might have saved myself a fair bit of money and time spent on other calculator apps. If you like to use RPN calculators and keystroke programming, this one deserves your attention. Pros - it’s a calculator first and foremost. There is no CAS or graphing to bloat the app. The stack and program listing windows make keeping track of things very easy. It looks good and the settings are straightforward and useful (thank you for allowing the option to mute the key sounds). Cons - none so far. ### 5/5 — Problème maj 2.13 *2018-09-08* Super appli que j’utilise depuis longtemps, mais la mise à jour 2.13 a réduit la taille de la hp25 et la met dans le coin haut gauche. Ce serait super de corriger ce bug. Y compris sur la hp21... **Developer response:** Bug fixed for both the 21 and 25 emulations - sorry about that. ### 5/5 — Jcc3rd RPN user *2016-05-10* I've used the SciRPN-25 for about 3 months. The calculator emulates the original HP25c accurately, but with more programmable steps. The panel showing the stack and register content make the calculator easier to use compared to the original. No bugs detected yet. The SciRPN-25 replaced my buggy HP-11c emulator. I've written my own programs including: combinations, permutations, amortization, and linear regression. Highly recommended for those who want to replace their aging or non-working Woodstock class HP calculators: 25, 25c, or 29c. In summary, I love this calculator. ### 5/5 — Perfectly Rendered! *2016-03-04* Accurate and beautiful recreation of best calculator HP ever made. Had a 25 and 29c in engin school, loved it. Still have my 43-year-old 29c but battery drains too fast to be usable. This app provides the look, feel and calculation ease of the original. Much better than the junk HP is selling these days. Thanks for taking the time and care to do it right. **Developer response:** Working on HP-29c ... ... Update: now there really is GO-29 ! --- *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 2026-09-04.*