# Fairlee Focus vs Modern RPN

The clearest difference is price: Fairlee Focus at Free against Modern RPN's $2.99. Fairlee Focus also leads on iOS requirement (15.0 vs 26.2). Modern RPN's advantage is update cadence (every 5 days vs every 3 months). On ads, in-app purchases and device support there is nothing between them.

Fairlee Focus is free to download; Modern RPN costs $2.99 up front. Neither carries in-app purchases, so what you see is what you pay.

Fairlee Focus ships an update every 3 months, Modern RPN every 5 days. The most recent releases landed on November 4, 2026 and November 6, 2026 respectively.

## The numbers

| Metric | Fairlee Focus | Modern RPN |
| --- | --- | --- |
| Price | **Free** | $2.99 |
| Rating | — | **[5.0 (1 ratings)](https://appshunter.io/ios/app/modern-rpn/id6760340697/reviews)** |
| Number of ratings | — | **1** |
| Positive reviews | — | 100.0% of reviews |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 3 months | **Every 5 days** |
| Monetization | — | Paid |
| Size | 132 MB | 2 MB |
| Requires iOS | **15.0** | 26.2 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [GOGov, Inc.](https://appshunter.io/developer/351223719) | [Kevin Flathers](https://appshunter.io/developer/1883973737) |

## What reviewers say

### Fairlee Focus

[App page](https://appshunter.io/ios/app/fairlee-focus/id6499055121)

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

**In-app purchases:** none


### Modern RPN

[App page](https://appshunter.io/ios/app/modern-rpn/id6760340697)

A minimalist reverse Polish notation calculator for iOS devices. It offers Standard, Binary, and Hex modes for quick calculations and programmer-friendly conversions, featuring a clean interface and a 4-level stack.

**Highlights:** Reverse Polish Notation (RPN) input, Standard, Binary, and Hex modes, 4-level visible stack, Calculation history, Saved session state, Clean dark interface

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is Fairlee Focus free?

Fairlee Focus is free to download, with no in-app purchases.

### Is Modern RPN free?

Modern RPN costs $2.99, with no in-app purchases.

### Do Fairlee Focus or Modern RPN have ads?

Neither Fairlee Focus nor Modern RPN shows ads.

### Which is updated more often, Fairlee Focus or Modern RPN?

Fairlee Focus ships an update every 3 months, and Modern RPN every 5 days. Most recently, Fairlee Focus was updated on November 4, 2026 and Modern RPN on November 6, 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.*