Overview

Rating:
4.90 +1
(79)
Version:
1.3.15
Last updated: 2026-05-05
Ranking
#162,315 516
Overall

Features & Capabilities

Plus42 is an advanced scientific programmable calculator based on Free42, a complete re-implementation of the HP-42S. It preserves the HP-42S capabilities while extending them with modern features and a Chrome-friendly interface.

Key enhancements include algebraic expressions similar to HP-27S/HP-17B/19B, attached units and conversions, organized program and variable storage, a larger resizable display, money-time value calculations, amortization schedules, and 2D plotting with zoom, pan, and integral/root-from-plot-point support.

User Growth & Download Statistics

By:
Thomas Okken
Rating:
4.90
(79)
1 new ratings
Version:
1.3.15 Last updated: 2026-05-05
Version code:
885258003
Creation date:
2022-04-28
Compatible devices:
Size:
11.45MB
Price:
9.99
URLs:
Website ,Privacy policy
Full description:
See detailed description
Source:
Apple Apps Store
Data ingested on:
2026-07-25
Compare stats and ranking:

Contact the developer

Chrome-Stats does not own this Apple app. Please use these information below to contact the Apple app developer.
Developed by:
Thomas Okken
Apple Apps Store
https://apps.apple.com/us/app/plus42/id1597963622
Website:
https://thomasokken.com/plus42/

User Reviews

Plus42 is widely praised for faithfully recreating the HP-42S RPN calculator on iPhone and iPad, delivering nostalgic fidelity, portability, and a polished, feature-rich experience that surpasses Free42. Reviewers value its faithful feel, the ability to have a powerful calculator in their pocket, and the strong graphics/UI. Many call it the best HP-inspired calculator app. Some note a programming issue, iPad multitasking limitations, and requests for more programming capabilities (e.g., TVM variables). Overall, user sentiment is highly positive with occasional feature requests.
Pros
  • Faithful HP-42S recreation with nostalgic fidelity
  • Portable/mobile access: always with you on iPhone/iPad
  • Rich feature set and enhancements (e.g., Dir and Eqn)
  • Beautiful, polished graphics and UI
  • Intuitive and easy to use for RPN users
Cons
Recent reviews
Don’t waste your money!
by Ab*****, 2026-05-09

Once you use an RPN calculator, you will never go back. The HP-42S beats the HP Prime in layout and ease of use for most task, and the enhancements in this implementation is great. I love having the (enhanced) HP-42S always with me on my iPhone whenever I need a calculator.
by Ca*****, 2026-01-12
View all user reviews ›

Best Plus42 Alternatives

Here are some Apple apps that are similar to Plus42: