# Scientific Calculator Plus 991 vs Statistics Formulas

The clearest difference is ads: Statistics Formulas at none against Scientific Calculator Plus 991's shown. Statistics Formulas also leads on update cadence (every 3 days vs fortnightly). Scientific Calculator Plus 991's advantage is device support (4 vs 2). On price, in-app purchases and iOS requirement there is nothing between them.

Both are free to download. Scientific Calculator Plus 991 sells 4 in-app purchases, starting at $1.99 per month and Statistics Formulas sells 7 one-off in-app purchases. Whichever you choose, the download price is not the number that matters.

Scientific Calculator Plus 991 ships an update fortnightly, Statistics Formulas every 3 days. The most recent releases landed on November 4, 2026 and October 30, 2026 respectively.

## The numbers

| Metric | Scientific Calculator Plus 991 | Statistics Formulas |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.7 (13K ratings)](https://appshunter.io/ios/app/scientific-calculator-plus-991/id1449106995/reviews)** | — |
| Number of ratings | **13K** | — |
| Positive reviews | 91.7% of reviews | — |
| In-app purchases | Yes | Yes |
| Ads | Yes | **No** |
| Update frequency | Fortnightly | **Every 3 days** |
| Monetization | Free with in-app purchases | — |
| Size | 169 MB | 23 MB |
| Requires iOS | **15** | 16.6 |
| Devices | **iPhone, iPad, iPod, Mac** | iPhone, iPad |
| Age rating | 12+ | 17+ |
| Developer | [Tran Duy](https://appshunter.io/developer/1449106994) | [NovaNext](https://appshunter.io/developer/1285557502) |

## What reviewers say

### Scientific Calculator Plus 991

[App page](https://appshunter.io/ios/app/scientific-calculator-plus-991/id1449106995)

This app is a powerful scientific calculator with graphing capabilities, a formula library, and a unit converter. It offers natural display input, advanced math functions for algebra, calculus, and statistics, and supports various number bases and formats.

**Highlights:** Natural display input, Graphing module, Formula library, Unit and currency converter, Algebra and calculus tools, Matrix and vector operations, Statistical calculations

**Features:** Family Sharing, Vision Pro support

**In-app purchases (4)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Calculator month subscription | $1.99 | per month |
| Calculator yearly subscription | $3.99 | per year |
| Calculator Premium | $5.99 | one-time |
| Calculator Pro | $5.99 | one-time |

**What reviewers like**

- 👍 Intuitive and easy to use
- 🚀 Powerful and feature-rich
- 💡 Customizable interface and settings
- 🔍 Extensive library of formulas and equations
- ⚙️ Handles complex math and scientific functions well

**What reviewers complain about**

- 🐛 Occasional bugs and input issues
- 🔀 Confusing layout and button placement
- 💰 Some advanced features locked behind paywall

**Reported bugs**

- Keyboard input stops working after switching screens
- Incorrect calculation results for certain operations
- App crashes on some devices after recent update

**Requested features**

- Add option to change display font and color
- Improve cursor control and editing capabilities
- Implement auto-simplification for complex expressions
- Add more handwriting font options
- Expand graphing and equation solving features


### Statistics Formulas

[App page](https://appshunter.io/ios/app/statistics-formulas/id6447047160)

**Features:** macOS Compatibility, Vision Pro support, iPhone Duo support

**In-app purchases (7)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Coffee | $0.99 | one-time |
| Remove Ads | $0.99 | one-time |
| Donate $3 | $2.99 | one-time |
| Donate $5 | $4.99 | one-time |
| Donate $10 | $9.99 | one-time |
| Donate $15 | $14.99 | one-time |
| Donate $20 | $19.99 | one-time |


## Frequently asked questions

### Is Scientific Calculator Plus 991 free?

Scientific Calculator Plus 991 is free to download, with in-app purchases available.

### Is Statistics Formulas free?

Statistics Formulas is free to download, with in-app purchases available.

### Do Scientific Calculator Plus 991 or Statistics Formulas have ads?

Scientific Calculator Plus 991 shows ads; Statistics Formulas does not.

### Which is updated more often, Scientific Calculator Plus 991 or Statistics Formulas?

Scientific Calculator Plus 991 ships an update fortnightly, and Statistics Formulas every 3 days. Most recently, Scientific Calculator Plus 991 was updated on November 4, 2026 and Statistics Formulas on October 30, 2026.

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*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*