# USA Unit Converter vs Calc ± Smart Widgets

The clearest difference is in-app purchases: USA Unit Converter at none against Calc ± Smart Widgets's 2. Calc ± Smart Widgets's advantage is update cadence (daily vs every 14 months). On price, ads, device support and iOS requirement there is nothing between them.

Both are free to download. Calc ± Smart Widgets sells 2 in-app purchases, starting at $1.99 per month. USA Unit Converter asks for nothing beyond the download.

USA Unit Converter ships an update every 14 months, Calc ± Smart Widgets daily. The most recent releases landed on October 25, 2026 and October 30, 2026 respectively.

## The numbers

| Metric | USA Unit Converter | Calc ± Smart Widgets |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 14 months | **Daily** |
| Size | 2 MB | 55 MB |
| Requires iOS | 17.0 | 17.0 |
| Devices | iPhone, iPad | iPhone, iPad |
| Age rating | 4+ | +4 |
| Developer | [Andrey Seleznev](https://appshunter.io/developer/1665252540) | [HKinfoway Technologies](https://appshunter.io/developer/1498599856) |

## What reviewers say

### USA Unit Converter

[App page](https://appshunter.io/ios/app/usa-unit-converter/id1669915305)

**Features:** macOS Compatibility

**In-app purchases:** none


### Calc ± Smart Widgets

[App page](https://appshunter.io/ios/app/calc-smart-widgets/id6745335333)

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

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Calc ± Pro Monthly | $1.99 | per month |
| Calc ± Pro Yearly | $12.99 | per year |


## Frequently asked questions

### Is USA Unit Converter free?

USA Unit Converter is free to download, with no in-app purchases.

### Is Calc ± Smart Widgets free?

Calc ± Smart Widgets is free to download, with in-app purchases available.

### Do USA Unit Converter or Calc ± Smart Widgets have ads?

Neither USA Unit Converter nor Calc ± Smart Widgets shows ads.

### Which is updated more often, USA Unit Converter or Calc ± Smart Widgets?

USA Unit Converter ships an update every 14 months, and Calc ± Smart Widgets daily. Most recently, USA Unit Converter was updated on October 25, 2026 and Calc ± Smart Widgets on October 30, 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.*