# Bolt Length vs MultiProtector

The clearest difference is in-app purchases: MultiProtector at none against Bolt Length's 1. MultiProtector also leads on ads (none vs shown) and update cadence (every 6 months vs every 20 months). On price and device support there is nothing between them.

Both are free to download. Bolt Length sells 1 one-off in-app purchase. MultiProtector asks for nothing beyond the download.

Bolt Length ships an update every 20 months, MultiProtector every 6 months. Both last shipped on October 8, 2026.

## The numbers

| Metric | Bolt Length | MultiProtector |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[3.0 (2 ratings)](https://appshunter.io/ios/app/bolt-length-nominal-length/id1042345193/reviews)** | — |
| Number of ratings | **2** | — |
| Positive reviews | 33.3% of reviews | — |
| In-app purchases | Yes | **No** |
| Ads | Yes | **No** |
| Update frequency | Every 20 months | **Every 6 months** |
| Monetization | Free with in-app purchases | — |
| Size | 6 MB | 151 MB |
| Requires iOS | 14.0 | **12.2** |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [mitsunori oishi](https://appshunter.io/developer/905649994) | [NETZSCH Pumpen & Systeme GmbH](https://appshunter.io/developer/1568447514) |

## What reviewers say

### Bolt Length

[App page](https://appshunter.io/ios/app/bolt-length-nominal-length/id1042345193)

This application helps calculate the length of metric coarse screws based on Japanese Industrial Standards. It is designed for mechanical design purposes and should be used at the user's own risk.

**Highlights:** Metric coarse screw length calculation, Conforms to Japanese Industrial Standards (JIS), Designed for mechanical design, User risk disclaimer

**Features:** macOS Compatibility, Family Sharing

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Hide Ads | $1.99 | one-time |


### MultiProtector

[App page](https://appshunter.io/ios/app/multiprotector/id1568447512)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is Bolt Length free?

Bolt Length is free to download, with in-app purchases available.

### Is MultiProtector free?

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

### Do Bolt Length or MultiProtector have ads?

Bolt Length shows ads; MultiProtector does not.

### Which is updated more often, Bolt Length or MultiProtector?

Bolt Length ships an update every 20 months, and MultiProtector every 6 months. Most recently, Bolt Length was updated on October 8, 2026 and MultiProtector on October 8, 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.*