RPN-35 SD 2.4 - App Store

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About RPN-35 SD

On January 4, 1972, Hewlett-Packard announced the HP-35, world's first scientific calculator small enough to fit in a pocket - more precisely, Bill Hewlett's shirt-pocket. The HP-35 was an immediate hit with students,...

On January 4, 1972, Hewlett-Packard announced the HP-35, world's first scientific calculator small enough to fit in a pocket - more precisely, Bill Hewlett's shirt-pocket. The HP-35 was an immediate hit with students, engineers, and scientists. Despite its steep price of $395 (about $3000 today), it sold ten times better than anticipated in the first year. Experience this unique calculator that won HP the prestigious "IEEE Milestone in Electrical Engineering and Computing" in 2009. Features: . Photo-realistic look-and-feel . Three skins: version 1, versions 2 & 3 (1973) and final version 4 (1974) . Vintage mode and Enhanced mode . Key-click and key-glow, both optional . Swipe left across display to correct number input errors . Cut/copy/paste display value . Display stack registers and memory registers . All decimal points but one light when iPhone battery charge drops below 5% Vintage mode In this mode, peculiarities of a real HP-35 are simulated: - original speed of operation - stack register Z copied to T on trig functions - leading zeros may be entered; zero can be made negative - a negative number may be entered by pressing CHS before or after the number - a keyboard entry or RCL immediately following STO does not raise the stack - for version 1 only: simulation of a number of known arithmetic bugs Enhanced mode - non-volatile stack and registers - use registers 1 through 9 with HP-45-like register arithmetic - register 0 works as LastX register

Version History • Improved compatibility with iPhone Air and iOS 26. 2.4 10/16/2025 • Faster startup – no delay until the first button press is recognized after switching on. 2.3 05/09/2025 • Redesigned Settings screen • Visual adjustments to iPhone 16 Pro and iPhone 16 Pro Max • RPN-35 SD requires iOS 12 or later 2.2 10/30/2024 • Haptics – Set the haptic feedback level in the calculator's settings. – „Sounds & Haptics“ / „System Haptics“ must be on in the iPhone's settings. – Note that iPads have no haptics engine. • Optimized Settings View for devices with Home button • Compatibility with iPhone 14 Pro 2.1 09/22/2022 Compatibility with iPhone 12 2.0.2 11/05/2020 Fixed bug: Calculations in scientific mode in regions not using "E" as exponent symbol (i.e. Sweden, Australia, Slovenia) would cause a crash. 2.0.1 03/18/2020 • If RPN-35 is set to HP-35 version v1 ("Red dot") and Vintage Mode is on: 1. Simulation of (rather weird) EEX key behavior, i.e. exponent not shown initially, CHS ignored after digit entry, no CHS toggling 2. Simulation of additional known calculation bugs. See website for details. • HP-35 version 4 shows correct logo and label at the bottom (on applicable iOS devices.) • Support for iOS 13 Dark Mode RPN-35 SD now requires iOS 11 or later. 2.0 01/25/2020 Emulation of known calculation bugs found in early HP-35 models (only if RPN-35 is set to HP-35 version v1 and Vintage Mode is on.) See website for details. 1.7 08/13/2019 • Changed "Undo digit" sound to same as found on other CuVee calculators • Many under-the-hood refinements • Support of late 2018 iPhones 1.6 01/07/2019 • Values containing blanks may be pasted into display 1.5.2 11/06/2017 • Improved compatibility with iPhone X Bug fix: • Incorrect app icon shown when installed on iPad 1.5.1 10/30/2017 • Improved trig functions for extremely small angles • Support for iOS 11 and iPhone X 1.5 10/24/2017 • Fixed sin(90°) sign error 1.4.1 01/19/2017 This update requires iOS 8 or later. • Improved results for SIN, COS, TAN with very large arguments • Decimal addition/subtraction for higher precision • Calculator sounds mix with background audio and have their own volume control 1.4 10/02/2016 • Fixes an issue where a result rounded up to 1, e.g. cos(0.0001), would be displayed as a decimal point only. 1.3.1 04/07/2016 • If audio is playing on start-up, RPN-35 SD will not produce any sounds 1.3 09/02/2015 • Added info about how to access settings screen • Fixed non-volatile memory not working 1.2 05/12/2015 • HP-35 version 1 (with red dot) added • For the purists: Settings and Info buttons may be set to invisible • Low-battery situation shows one decimal point unlit, as depicted in the HP-35 User's Manual 1.1 04/08/2015 1.0 01/18/2015

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Previous Versions

Here you can find the changelog of RPN-35 SD since it was posted on our website on 2016-09-26 22:04:31. The latest version is 2.4 and it was updated on 2026-06-28 06:48:00. See below the changes in each version.

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