# TLV ToolBox vs Fit Tolerance ISO

The clearest difference is rating: Fit Tolerance ISO at 5.0 against TLV ToolBox's 4.5. TLV ToolBox's advantage is ads (none vs shown) and update cadence (every 4 months vs every 12 months). On price, in-app purchases and device support there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

Fit Tolerance ISO holds the better App Store score, 5.0 against 4.5. Both are backed by a comparable volume of ratings — 8 and 2 respectively.

TLV ToolBox ships an update every 4 months, Fit Tolerance ISO every 12 months. The most recent releases landed on November 6, 2026 and November 2, 2026 respectively.

## The numbers

| Metric | TLV ToolBox | Fit Tolerance ISO |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [4.5 (8 ratings)](https://appshunter.io/ios/app/tlv-toolbox/id653406777/reviews) | **[5.0 (2 ratings)](https://appshunter.io/ios/app/fit-tolerance-iso/id1251895012/reviews)** |
| Number of ratings | **8** | 2 |
| Positive reviews | 75.0% of reviews | — |
| In-app purchases | No | No |
| Ads | **No** | Yes |
| Update frequency | **Every 4 months** | Every 12 months |
| Monetization | **Free** | Ad-supported |
| Size | 4 MB | 51 MB |
| Requires iOS | **9.3** | 15.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [TLV CO.,LTD.](https://appshunter.io/developer/653406780) | [Yasar Yucel Yesilbag](https://appshunter.io/developer/1251895011) |

## What reviewers say

### TLV ToolBox

[App page](https://appshunter.io/ios/app/tlv-toolbox/id653406777)

This utility app transforms your mobile device into a portable steam calculation tool. It assists with onsite calculations for control valve stations, condensate recovery systems, and various maintenance tasks, reducing the need for multiple trips.

**Highlights:** Steam Tables (saturated and superheated), Steam Pipe Sizing, Condensate Pipe Sizing, Heating Calculations, Cv and Kv Values, Stall Point

**Features:** macOS Compatibility

**In-app purchases:** none


### Fit Tolerance ISO

[App page](https://appshunter.io/ios/app/fit-tolerance-iso/id1251895012)

Calculates engineering tolerances for various mechanical components based on ISO and ANSI standards. It determines size limits, deviations, and fit types for holes and shafts, offering schematic representations of fits.

**Highlights:** Calculates engineering tolerances, Supports ISO and ANSI standards, Determines clearance, transition, and interference fits, Provides schematic fit representations, Includes preferred tolerances and fits, Works with metric units

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

**In-app purchases:** none


## Frequently asked questions

### Is TLV ToolBox free?

TLV ToolBox is free to download, with no in-app purchases.

### Is Fit Tolerance ISO free?

Fit Tolerance ISO is free to download, with no in-app purchases.

### Which has better reviews, TLV ToolBox or Fit Tolerance ISO?

Fit Tolerance ISO is rated higher. TLV ToolBox averages 4.5 out of 5 from 8 ratings, while Fit Tolerance ISO averages 5.0 from 2 ratings.

### Do TLV ToolBox or Fit Tolerance ISO have ads?

Fit Tolerance ISO shows ads; TLV ToolBox does not.

### Which is updated more often, TLV ToolBox or Fit Tolerance ISO?

TLV ToolBox ships an update every 4 months, and Fit Tolerance ISO every 12 months. Most recently, TLV ToolBox was updated on November 6, 2026 and Fit Tolerance ISO on November 2, 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.*