# ShiftZen vs Calto

The clearest difference is in-app purchases: Calto at none against ShiftZen's 3. On price, update cadence, ads and device support there is nothing between them.

Both are free to download. ShiftZen sells 3 in-app purchases, starting at $5.99 per month. Calto asks for nothing beyond the download.

ShiftZen ships an update every 11 days, Calto every 9 days. The most recent releases landed on September 20, 2026 and August 5, 2026 respectively.

## The numbers

| Metric | ShiftZen | Calto |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | Every 11 days | **Every 9 days** |
| Size | 2 MB | 29 MB |
| Requires iOS | 15.6 | 15.6 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Sertac Gul](https://appshunter.io/developer/1863083549) | [JONGWOO PARK](https://appshunter.io/developer/1873952653) |

## What reviewers say

### ShiftZen

[App page](https://appshunter.io/ios/app/shiftzen/id6757182605)

**Features:** macOS Compatibility

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| ShiftZen Pro Aylık | $5.99 | per month |
| ShiftZen Pro Quarterly | $15.99 | per 3 months |
| ShiftZen Pro Yearly | $59.99 | per year |


### Calto

[App page](https://appshunter.io/ios/app/calto-note-calculator/id6758614596)

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

**In-app purchases:** none


## Frequently asked questions

### Is ShiftZen free?

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

### Is Calto free?

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

### Do ShiftZen or Calto have ads?

Neither ShiftZen nor Calto shows ads.

### Which is updated more often, ShiftZen or Calto?

ShiftZen ships an update every 11 days, and Calto every 9 days. Most recently, ShiftZen was updated on September 20, 2026 and Calto on August 5, 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.*