# Is it Prime? vs OnClock

The clearest difference is price: Is it Prime? at Free against OnClock's $0.99. Is it Prime? also leads on rating (3.2 vs 2.5) and review sentiment (71% vs 63%). OnClock's advantage is update cadence (every 3 weeks vs every 74 months). On ratings volume, ads, in-app purchases and device support there is nothing between them.

Is it Prime? is free to download; OnClock costs $0.99 up front. Neither carries in-app purchases, so what you see is what you pay.

Is it Prime? holds the better App Store score, 3.2 against 2.5. Both are backed by a comparable volume of ratings — 5 and 2 respectively. Written reviews point the same way: 71% of Is it Prime?'s written reviews are positive against 63% of OnClock's.

Is it Prime? ships an update every 74 months, OnClock every 3 weeks. Both last shipped on September 25, 2026.

## The numbers

| Metric | Is it Prime? | OnClock |
| --- | --- | --- |
| Price | **Free** | $0.99 |
| Rating | **[3.2 (5 ratings)](https://appshunter.io/ios/app/is-it-prime/id326095651/reviews)** | [2.5 (2 ratings)](https://appshunter.io/ios/app/onclock-widget/id1533102000/reviews) |
| Number of ratings | **5** | 2 |
| Positive reviews | **71.4% of reviews** | 62.5% of reviews |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 74 months | **Every 3 weeks** |
| Monetization | **Free** | Paid |
| Size | 1 MB | 13 MB |
| Requires iOS | 15.0 | **14.0** |
| Devices | **iPhone, iPad, iPod** | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Wismar](https://appshunter.io/developer/307757950) | [AHN YOONJI](https://appshunter.io/developer/1056120766) |

## What reviewers say

### Is it Prime?

[App page](https://appshunter.io/ios/app/is-it-prime/id326095651)

Enter any number to instantly determine if it is a prime number or not. This straightforward utility provides a quick answer to your mathematical curiosity.

**Highlights:** Prime number identification, Simple number input, Instant yes/no results

**Features:** macOS Compatibility

**In-app purchases:** none


### OnClock

[App page](https://appshunter.io/ios/app/onclock-widget/id1533102000)

Customize your home screen with unique clock widgets. Choose from designer fonts, personalized gradient colors, and adjustable text sizes. Enhance your widget with a background image for a personalized look.

**Highlights:** 20 designer font types, Customizable gradient colors, Adjustable time and date text size, Background image support, Home screen widget decoration

**Features:** Vision Pro support

**In-app purchases:** none


## Frequently asked questions

### Is Is it Prime? free?

Is it Prime? is free to download, with no in-app purchases.

### Is OnClock free?

OnClock costs $0.99, with no in-app purchases.

### Which has better reviews, Is it Prime? or OnClock?

Is it Prime? is rated higher. Is it Prime? averages 3.2 out of 5 from 5 ratings, while OnClock averages 2.5 from 2 ratings.

### Do Is it Prime? or OnClock have ads?

Neither Is it Prime? nor OnClock shows ads.

### Which is updated more often, Is it Prime? or OnClock?

Is it Prime? ships an update every 74 months, and OnClock every 3 weeks. Most recently, Is it Prime? was updated on September 25, 2026 and OnClock on September 25, 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.*