HP vs AcoustiCalc
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
HP
Emulates classic Hewlett Packard RPN scientific calculators from the 1970s. Experience the original HP-35, HP-45, and HP-21 models on your iPhone.
- RPN calculator emulation
- HP-35 model
- HP-45 model
- HP-21 model
- Classic scientific calculator interface
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The classic Hewlett Packard RPN (Reverse Polish Notation) calculators. - HP-35, HP-45. First pocket scientific calculators (1972). - HP-21. 2nd gen of the HP-35 (1975)
AcoustiCalc
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AcoustiCalc is the ultimate toolkit designed for architects, engineering firms, and acousticians. Instantly calculate the reverberation time (RT60) via Sabine's Formula or estimate the sound insulation of walls using the Mass Law. Premium B2B Features: - Predictive acoustic modeling with interactive graphs. - Expert local database: 300+ materials with Alpha absorption coefficients (125Hz-4kHz) certified ISO 354. - White Label PDF Report Generator for direct client delivery. - Integrated Live SPL Meter. - Metric and Imperial system support. 100% Offline. Zero Cloud. Compliance and industrial secrecy guaranteed. Legal Disclaimer: Simulations are predictive and do not replace certified in-situ measurements.
Screenshots
Verdict
The clearest difference is price: HP at Free against AcoustiCalc's $3.99. AcoustiCalc's advantage is update cadence (daily vs every 11 days). On ads, in-app purchases, device support and iOS requirement 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
HP is free to download; AcoustiCalc costs $3.99 up front. Neither carries in-app purchases, so what you see is what you pay.
HP ships an update every 11 days, AcoustiCalc daily. Both last shipped on October 8, 2026.
| Parameter | HP | AcoustiCalc |
|---|---|---|
| Price | Free — better | $3.99 |
| Rating | 5.0 (5 ratings) — better | — |
| Positive reviews | 100.0% of reviews | — |
| Number of ratings | 5 — better | — |
| Update frequency | Every 11 days | Daily — better |
| Ads | No | No |
| In-app purchases | No | No |
| Monetization | Free | — |
| Devices | iPhone | iPhone, iPad — better |
| Requires iOS | 17.2 | 17 — better |
| Further details — not scored | ||
| Size | 2 MB | 43 MB |
| Age rating | 4+ | 4+ |
| Developer | Enrique Haro | TRIMECH Dhaker |
In-app purchases
HP
No in-app purchases
AcoustiCalc
No in-app purchases
