# PrefixCalc vs Shift Work Alarm

The clearest difference is in-app purchases: PrefixCalc at none against Shift Work Alarm's 2. PrefixCalc also leads on device support (3 vs 1) and iOS requirement (12.0 vs 26.0). On price and ads there is nothing between them.

Both are free to download. Shift Work Alarm sells 2 in-app purchases, starting at $0.99 per month. PrefixCalc asks for nothing beyond the download.

## The numbers

| Metric | PrefixCalc | Shift Work Alarm |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[5.0 (1 ratings)](https://appshunter.io/ios/app/shift-work-alarm-roster/id6808283069/reviews)** |
| Number of ratings | — | **1** |
| Positive reviews | — | 100.0% of reviews |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | — | Weekly |
| Monetization | — | Freemium |
| Size | 28 MB | 11 MB |
| Requires iOS | **12.0** | 26.0 |
| Devices | **iPhone, iPad, iPod** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [YONAGARE LAB](https://appshunter.io/developer/1810986554) | [秋丽 陈](https://appshunter.io/developer/6803737891) |

## What reviewers say

### PrefixCalc

[App page](https://appshunter.io/ios/app/prefixcalc/id6748650037)

**Features:** macOS Compatibility

**In-app purchases:** none


### Shift Work Alarm

[App page](https://appshunter.io/ios/app/shift-work-alarm-roster/id6808283069)

This alarm clock is designed for individuals with non-traditional work schedules. It offers customizable alarms that can automatically skip holidays and follow specific shift patterns, ensuring you wake up on workdays and rest on days off. It also includes a smart calendar and spoken reminders for various needs.

**Highlights:** Shift-based alarms, Automatic holiday skipping, Customizable rotation patterns, Spoken reminders, Smart calendar view, Rings through silent mode

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

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Shift Pro Monthly | $0.99 | per month |
| Shift Alarm Pro | $9.99 | per year |


## Frequently asked questions

### Is PrefixCalc free?

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

### Is Shift Work Alarm free?

Shift Work Alarm is free to download, with in-app purchases available.

### Do PrefixCalc or Shift Work Alarm have ads?

Neither PrefixCalc nor Shift Work Alarm shows ads.

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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.*