# Simple Hex Calc vs Fit Tolerance ISO Pro

The clearest difference is review sentiment: Simple Hex Calc at 94% against Fit Tolerance ISO Pro's 50%. Simple Hex Calc also leads on update cadence (every 5 months vs every 12 months) and ratings volume (8 vs 1). Fit Tolerance ISO Pro's advantage is rating (5.0 vs 4.5) and iOS requirement (15.0 vs 27.0). On price, ads, in-app purchases and monetization model there is nothing between them.

Simple Hex Calc costs $0.99 and Fit Tolerance ISO Pro $0.99 up front. Neither carries in-app purchases, so what you see is what you pay.

Fit Tolerance ISO Pro holds the better App Store score, 5.0 against 4.5. That said, the two scores are not equally well evidenced: Simple Hex Calc has 8 ratings behind it against 1, so its average is the more settled of the two. Written reviews complicate that: 94% of Simple Hex Calc's written reviews are positive against 50% of Fit Tolerance ISO Pro's, so the app with the better star average is not the one people write more warmly about.

Simple Hex Calc ships an update every 5 months, Fit Tolerance ISO Pro every 12 months. The most recent releases landed on October 27, 2026 and October 24, 2026 respectively.

## The numbers

| Metric | Simple Hex Calc | Fit Tolerance ISO Pro |
| --- | --- | --- |
| Price | $0.99 | $0.99 |
| Rating | [4.5 (8 ratings)](https://appshunter.io/ios/app/simple-hex-calc/id335773208/reviews) | **[5.0 (1 ratings)](https://appshunter.io/ios/app/fit-tolerance-iso-pro/id1397159146/reviews)** |
| Number of ratings | **8** | 1 |
| Positive reviews | **94.4% of reviews** | 50.0% of reviews |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Every 5 months** | Every 12 months |
| Monetization | Paid | Paid |
| Size | 1 MB | 47 MB |
| Requires iOS | 27.0 | **15.0** |
| Devices | iPhone, iPad | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Hiroki Ishiura](https://appshunter.io/developer/335773211) | [Yasar Yucel Yesilbag](https://appshunter.io/developer/1251895011) |

## What reviewers say

### Simple Hex Calc

[App page](https://appshunter.io/ios/app/simple-hex-calc/id335773208)

This utility app provides IT programmers with a pocket calculator for performing arithmetic and logical operations on numbers in various bases. It offers extensive configuration options for bit length, signed/unsigned modes, and data display formats, with a reference manual included.

**Highlights:** Arithmetic and logical operations, Multiple number base support (2/8/10/16), Bit shift, rotate, set, clear, and order operations, Memory operations (save, load, swap), Configurable bit length and signed/unsigned modes, Cut, copy, and paste results, Reference manual included

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

**In-app purchases:** none


### Fit Tolerance ISO Pro

[App page](https://appshunter.io/ios/app/fit-tolerance-iso-pro/id1397159146)

Calculate engineering tolerances for various mechanical components like bearings, shafts, and housings. It adheres to ISO and ANSI standards, providing size limits, deviations, and fit types. Visual representations of fits are also generated.

**Highlights:** Calculate engineering tolerances, Supports ISO and ANSI standards, Determines clearance, transition, and interference fits, Provides schematic fit representations, Includes preferred tolerances and fits, Calculates size limits and deviations

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

**In-app purchases:** none


## Frequently asked questions

### Is Simple Hex Calc free?

Simple Hex Calc costs $0.99, with no in-app purchases.

### Is Fit Tolerance ISO Pro free?

Fit Tolerance ISO Pro costs $0.99, with no in-app purchases.

### Which has better reviews, Simple Hex Calc or Fit Tolerance ISO Pro?

Fit Tolerance ISO Pro is rated higher. Simple Hex Calc averages 4.5 out of 5 from 8 ratings, while Fit Tolerance ISO Pro averages 5.0 from 1 ratings.

### Do Simple Hex Calc or Fit Tolerance ISO Pro have ads?

Neither Simple Hex Calc nor Fit Tolerance ISO Pro shows ads.

### Which is updated more often, Simple Hex Calc or Fit Tolerance ISO Pro?

Simple Hex Calc ships an update every 5 months, and Fit Tolerance ISO Pro every 12 months. Most recently, Simple Hex Calc was updated on October 27, 2026 and Fit Tolerance ISO Pro on October 24, 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.*