HP21 scientific RPN calculator
9.1 14
v2.9 by Milan Cisár
About HP21
HP21 (Package Name: appinventor.ai_milancisar72.HP21) is developed by Milan Cisár and the latest version of HP21 scientific RPN calculator 2.9 was updated on May 7, 2019. HP21 scientific RPN calculator is in the category of Tools. You can check all apps from the developer of HP21 scientific RPN calculator and find 44 alternative apps to HP21 scientific RPN calculator on Android. Currently this app is for free. This app can be downloaded on Android 2.1+ on APKFab or Google Play. All APK/XAPK files on APKFab.com are original and 100% safe with fast download.
The HP-21 was a scientific calculator produced by Hewlett-Packard between 1975 and 1978. It was designed as a replacement for the HP-35, and was the first from so called Second Generation Handheld Calculators.
As with most HP calculators then and now, the HP-21 used RPN entry logic, with a four-level stack. It also had a single user-accessible memory register. A shift key provided access to functions whose legends were printed on the fronts of the tall trapezoidal keys.
To enhance practical usability, display was modified to show both X and Y register. Also I have eliminated mechanical DEG/RAD switch and moved the function under DSP button.
HP21 has few big enough buttons to be used comfortably on mobile devices.
As with most HP calculators then and now, the HP-21 used RPN entry logic, with a four-level stack. It also had a single user-accessible memory register. A shift key provided access to functions whose legends were printed on the fronts of the tall trapezoidal keys.
To enhance practical usability, display was modified to show both X and Y register. Also I have eliminated mechanical DEG/RAD switch and moved the function under DSP button.
HP21 has few big enough buttons to be used comfortably on mobile devices.
HP21 2.9 Update
Re-compiled to support Android 9
Read More
HP21 Features
Previous Versions More
HP21 scientific RPN calculator
2.9
APK
May 8, 2019
3.78 MB
Requires Android: Android 2.1+
Screen DPI: 160-640dpi
SHA1: a89c07bd770de08bb99d0c98fd70c15dd78b20b7
Size: 3.78 MB
What's New:
Re-compiled to support Android 9
HP21 scientific RPN calculator
2.7
APK
December 14, 2016
2.28 MB
Requires Android: Android 1.6+
Screen DPI: 160dpi
SHA1: 645167c4dfd17c7afbbb2ab501d39fbffc00f898
Size: 2.28 MB
What's New:
2.7. Y^X complex result bug fixed (Error is shown for COmplex result)
2.6. touch area re-alligned to buttons properly - thank you Eric
2.5. Can enter number by EEX button directly
2.4. To improve usablity - now running in full screen
2.6. touch area re-alligned to buttons properly - thank you Eric
2.5. Can enter number by EEX button directly
2.4. To improve usablity - now running in full screen
HP21 scientific RPN calculator
2.6
APK
November 12, 2016
2.28 MB
Requires Android: Android 1.6+
Screen DPI: 160dpi
SHA1: 397b3b790da19f361f8bdcc216dd4d0824712fd6
Size: 2.28 MB
What's New:
2.6. touch area re-alligned to buttons properly - thank you Eric
2.5. Can enter number by EEX button directly
2.4. To improve usablity - now running in full screen
2.5. Can enter number by EEX button directly
2.4. To improve usablity - now running in full screen
HP21 scientific RPN calculator
2.5
APK
November 9, 2016
2.28 MB
Requires Android: Android 1.6+
Screen DPI: 160dpi
SHA1: 5152e09ed17fd82ddf4eb0c7cb5e1497311c8b30
Size: 2.28 MB
What's New:
2.5. Can enter number by EEX button directly
2.4. To improve usablity - now running in full screen
2.4. To improve usablity - now running in full screen
More Information
Package Name:
Update Date:
2019-05-07
Latest Version:
2.9
Need Update:
Requirements:
Android 2.1+
Report:
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