Software Features and Description
1. GO-21 SciRPN simulates the venerable HP-21 Pocket Scientific Calculator from 1975.
2. Virtually indistinguishable from the real item in operation, GO-21 is a powerful yet simple retro calculator.
3. Liked GO-21 SciRPN? here are 5 Utilities apps like GO-25 SciRPN; GO-29 SciRPN; Gboard – the Google Keyboard; Google Chrome;
Download and install GO-21 SciRPN on your computer
GET Compatible PC App
| App |
Download |
Rating |
Maker |
 GO-21 SciRPN |
Get App ↲ |
12
4.92 |
BigCatOs |
Or follow the guide below to use on PC:
Select Windows version:
- Windows 10
- Windows 11
Install GO-21 SciRPN app on your Windows in 4 steps below:
- Download an Android emulator for PC:
Get either Bluestacks or the Nox App >> . We recommend Bluestacks because you can easily find solutions online if you run into problems while using it. Download Bluestacks PC software Here >> .
- Install the emulator:
On your computer, goto the Downloads folder » click to install Bluestacks.exe or Nox.exe » Accept the License Agreements » Follow the on-screen prompts to complete installation.
- Using GO-21 SciRPN on PC [Windows 10/ 11]:
- Open the Emulator app you installed » goto its search bar and search "GO-21 SciRPN"
- The search will reveal the GO-21 SciRPN app icon. Open, then click "Install".
- Once GO-21 SciRPN is downloaded inside the emulator, locate/click the "All apps" icon to access a page containing all your installed applications including GO-21 SciRPN.
- Now enjoy GO-21 SciRPN on PC.
Download a Compatible APK for PC
Download on Windows 11
For Windows 11, check if there's a native GO-21 SciRPN Windows app here » ». If none, follow the steps below:
- To get started, Download the OpenPC software »
- Upon installation, open OpenPC app » goto "Playstore on PC" » click "Configure_Download" button. This will auto-download and install PlayStore on your computer.
- To use GO-21 SciRPN,
- Login to the PlayStore we just installed
- Search for "GO-21 SciRPN" » then Click "Install".
- GO-21 SciRPN will now be available on your Windows start-menu.
| Minimum requirements |
Recommended |
- 8GB RAM
- SSD Storage
- Processor: Intel Core i3, AMD Ryzen 3000
- Architecture: x64 or ARM64
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Get GO-21 SciRPN on Apple macOS
Download on Android: Download Android
✔ Pros:
- Delightful and easy to use
- Fast app switching works well
- Display and buttons are easy to see and use
- Swiping to see the entire stack is useful
- Built-in help is excellent
- Ability to "commify" numbers is a favorite added feature
- Very good reproduction of the HP-21's look and functions
- Useful for quick and straightforward calculations
☹ Cons:
Top Pcmac Reviews
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Delightful
By joemeyer (Pcmac user)
I was 18 when the HP-21 was released but did not buy one until years later when I was in College (I was in the US Army until age 21). This iPhone version is delightful to use and it works very well on my iTouch with the latest OS and indeed fast app switching works well. The display and buttons are easy to see and use. Swiping to see the entire stack is useful. Thanks for writing this app.
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Great Improvement on a Classic Calculator
By zcave (Pcmac user)
I used an HP-21 calculator in college back in the late 70's and early 80's. The rectangular-to-polar and polar-to-rectangular conversions were a lifesaver for an engineering student back then. This app is a great update to the original. The built-in help is excellent too. The ability to "commify" numbers is my favorite added feature. The developer is also very responsive.
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Return with us now to the days of yesteryear
By Noneblank Nickname (Pcmac user)
I bought an HP-21 during my third semester of college in 1976. At that time they were still teaching students how to use a slide rule.
The app is a very good reproduction of the HP-21's look and functions/functionality. I has the functions I want and doesn't have a lot of functions that I don't use. It has a useful Help file.
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Great implimentation!
By Bob RJB (Pcmac user)
A Classic! Just like my old HP-21 -- even to the realistic LED display. I have at least a dozen RPN calculators (both real and as iPhone Apps). Many are much more complex with lots of advanced features. But, if you are a RPN user, this HP-21 App is just perfect for going to for quick straight forward calculations. It has become my most used calculator.
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