Idea Hack vs RPN
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
Idea Hack
This app helps spark creativity by generating three random keywords to inspire new ideas. Users can register their own keywords and use the tool to brainstorm solutions or concepts, saving their thoughts in a memo field.
- Generate random keywords
- Create custom keyword lists
- Brainstorm ideas based on keywords
- Save ideas to memo
- Supports iPhone, iPad, iPod
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The idea is not float ... Submit ideas until tomorrow ... At that time, this app It is an application that idea gives rise. It is a tool to help the idea of creation. Ideas is important. It is also possible to change the world in one idea. By utilizing the three keywords you can create an idea that did not come up until now. Head will activate only the keyword than thinking through the use randomly. ---------------------------- How to use ---------------------------- As much as you can be registered keywords related to it. ※ There are also unexpected ideas and to register a keyword that are not relevant are created. Start the idea hack tool. Three keywords will come out, so consider the relevant ideas. Write to the memo field that noticed. When it does not come out and go to the next keyword. Notice when many of the ideas have been created.
RPN
This app is a photo-realistic simulation of a classic Hewlett-Packard programmable business calculator. It offers advanced programming features, extensive register memory, and a library of pre-installed programs for various financial and statistical calculations.
- Photo-realistic look-and-feel
- Programmable with subroutines and flags
- 20 registers with unlimited store/recall
- Indirect register addressing
- Program library and sharing
- Financial and statistical functions
- Date and calendar calculations
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RPN-38 CX is the first photo-realistic simulation of Hewlett-Packard's popular high-end programmable business calculator HP-38C for the iPhone. Produced from 1979 through 1983, it was the "Chive" member of the third-generation HP calculators known as the "Spice" series. While the simulator works like the original calculator, a number of carefully designed extensions make it a lot easier to use. RPN-38 CX is fully compatible with the HP-12C, except for calculations and programs involving Bonds and Depreciation. Features: • Photo-realistic look-and-feel • Programmable (99 steps, program memory not shared with register memory) • Subroutines, flags, loop control, extended conditional branching • Insert and delete steps with automatic address correction • 20 registers, "continuous", with unlimited store/recall arithmetic • Indirect register addressing • Register view • Program listing view • Program library view • Additional functions (nominal and effective interest rate) • Shortcuts for often-used key combinations • Store and retrieve any number of programs • Sharing: e-mail, AirDrop, Dropbox, copy, paste, print • 40 programs pre-installed Calculator functions: • Percentage (%, ∆%, %Total) • Simple and Compound Interest • Optional odd periods (like HP-12) • Nominal/Effective interest rate conversion • Amortization • Discounted Cash Flow Analysis • Net Present Value, Internal Rate of Return • Date and Calendar (actual or 30/360 day basis) • Statistics (mean, weighted mean, standard deviation) • Linear Regression • Additional functions not found on the HP-38: - Subroutines, flags, loop control, random number, Pi, Log, x² and more Details: cuveesoft.ch/rpn38
Screenshots
Verdict
The clearest difference is review sentiment: RPN at 100% against Idea Hack's 50%. RPN also leads on rating (5.0 vs 3.0) and ratings volume (6 vs 1). Idea Hack's advantage is price (Free vs $1.99) and update cadence (every 5 days vs every 2 months). On ads, in-app purchases and device support there is nothing between them.
Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS
Idea Hack is free to download; RPN costs $1.99 up front. Neither carries in-app purchases, so what you see is what you pay.
RPN holds the better App Store score, 5.0 against 3.0. That said, the two scores are not equally well evidenced: RPN has 6 ratings behind it against 1, so its average is the more settled of the two. Written reviews point the same way: 50% of Idea Hack's written reviews are positive against 100% of RPN's.
Idea Hack ships an update every 5 days, RPN every 2 months. The most recent releases landed on October 17, 2026 and October 12, 2026 respectively.
| Parameter | Idea Hack | RPN |
|---|---|---|
| Price | Free — better | $1.99 |
| Rating | 3.0 (1 ratings) | 5.0 (6 ratings) — better |
| Positive reviews | 50.0% of reviews | 100.0% of reviews — better |
| Number of ratings | 1 | 6 — better |
| Update frequency | Every 5 days — better | Every 2 months |
| Ads | No | No |
| In-app purchases | No | No |
| Monetization | Free — better | Paid |
| Devices | iPhone, iPad, iPod — better | iPhone, iPod |
| Requires iOS | 8.0 — better | 12.0 |
| Further details — not scored | ||
| Size | 23 MB | 12 MB |
| Age rating | 4+ | 4+ |
| Developer | TAKAHIRO AYA | CuVee Software |
Customer experience
Idea Hack
RPN
In-app purchases
Idea Hack
No in-app purchases
RPN
No in-app purchases









