# Robot Reading vs f(x) Calc

The clearest difference is price: f(x) Calc at Free against Robot Reading's $2.99. f(x) Calc also leads on update cadence (every 10 days vs every 6 weeks). Robot Reading's advantage is in-app purchases (none vs 1) and iOS requirement (13.0 vs 16.6). On rating, ratings volume, ads and monetization model there is nothing between them.

f(x) Calc is free to download; Robot Reading costs $2.99 up front. f(x) Calc sells 1 one-off in-app purchase. Robot Reading asks for nothing beyond the download.

On the App Store both sit at effectively the same score — 5.0 for Robot Reading against 5.0 for f(x) Calc. Both are backed by a comparable volume of ratings — 2 and 1 respectively.

Robot Reading ships an update every 6 weeks, f(x) Calc every 10 days. The most recent releases landed on September 19, 2026 and September 23, 2026 respectively.

## The numbers

| Metric | Robot Reading | f(x) Calc |
| --- | --- | --- |
| Price | $2.99 | **Free** |
| Rating | [5.0 (2 ratings)](https://appshunter.io/ios/app/robot-reading-learning-games/id6737028095/reviews) | [5.0 (1 ratings)](https://appshunter.io/ios/app/fx-calc/id6760609257/reviews) |
| Number of ratings | **2** | 1 |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 6 weeks | **Every 10 days** |
| Monetization | Free | Free |
| Size | 295 MB | 5 MB |
| Requires iOS | **13.0** | 16.6 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Thomas Green](https://appshunter.io/developer/1858521630) | [David Russell](https://appshunter.io/developer/1104864276) |

## What reviewers say

### Robot Reading

[App page](https://appshunter.io/ios/app/robot-reading-learning-games/id6737028095)

This app offers a free, ad-free phonics program for children aged 3-9 to learn reading and writing. It uses evidence-based methods like Systematic Synthetic Phonics and the Science of Reading to build foundational literacy skills through engaging games and interactive lessons.

**Highlights:** Systematic Synthetic Phonics approach, Interactive reading and writing games, Letter-sound recognition, Blending and segmenting practice, Sight word recognition, Sentence building, Full lifetime access

**Features:** macOS Compatibility

**In-app purchases:** none


### f(x) Calc

[App page](https://appshunter.io/ios/app/fx-calc/id6760609257)

A full-featured scientific calculator designed for math and science students. It offers natural math entry and includes built-in examples to aid learning. A simplified Junior mode is available for everyday use.

**Highlights:** Natural Maths entry, Built-in learning examples, Junior mode for everyday use, Ideal for math and science study, Full-featured scientific calculator

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Full Access | Free | one-time |


## Frequently asked questions

### Is Robot Reading free?

Robot Reading costs $2.99, with no in-app purchases.

### Is f(x) Calc free?

f(x) Calc is free to download, with in-app purchases available.

### Which has better reviews, Robot Reading or f(x) Calc?

Robot Reading and f(x) Calc are both rated 5.0 out of 5 on the App Store, from 2 and 1 ratings respectively.

### Do Robot Reading or f(x) Calc have ads?

Neither Robot Reading nor f(x) Calc shows ads.

### Which is updated more often, Robot Reading or f(x) Calc?

Robot Reading ships an update every 6 weeks, and f(x) Calc every 10 days. Most recently, Robot Reading was updated on September 19, 2026 and f(x) Calc on September 23, 2026.

---

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