# Smart Unit Conversion vs Lennik

The clearest difference is in-app purchases: Lennik at none against Smart Unit Conversion's 1. Lennik also leads on ads (none vs shown) and update cadence (fortnightly vs every 15 months). Smart Unit Conversion's advantage is device support (3 vs 1) and iOS requirement (13.4 vs 16.4). On price there is nothing between them.

Both are free to download. Smart Unit Conversion sells 1 in-app purchase, starting at $1.99 per year. Lennik asks for nothing beyond the download.

Smart Unit Conversion ships an update every 15 months, Lennik fortnightly. The most recent releases landed on November 7, 2026 and November 14, 2026 respectively.

## The numbers

| Metric | Smart Unit Conversion | Lennik |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | Yes | **No** |
| Ads | Yes | **No** |
| Update frequency | Every 15 months | **Fortnightly** |
| Size | 41 MB | 77 MB |
| Requires iOS | **13.4** | 16.4 |
| Devices | **iPhone, iPad, iPod** | iPhone |
| Age rating | 17+ | 12+ |
| Developer | [Yui Lau](https://appshunter.io/developer/1791465155) | [Vlaamse overheid](https://appshunter.io/developer/664577169) |

## What reviewers say

### Smart Unit Conversion

[App page](https://appshunter.io/ios/app/smart-unit-conversion/id1643381985)

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| 1 Year | $1.99 | per year |


### Lennik

[App page](https://appshunter.io/ios/app/lennik/id6670781265)

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

**In-app purchases:** none


## Frequently asked questions

### Is Smart Unit Conversion free?

Smart Unit Conversion is free to download, with in-app purchases available.

### Is Lennik free?

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

### Do Smart Unit Conversion or Lennik have ads?

Smart Unit Conversion shows ads; Lennik does not.

### Which is updated more often, Smart Unit Conversion or Lennik?

Smart Unit Conversion ships an update every 15 months, and Lennik fortnightly. Most recently, Smart Unit Conversion was updated on November 7, 2026 and Lennik on November 14, 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.*