Is it Prime? vs OnClock
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
Is it Prime?
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.
- Prime number identification
- Simple number input
- Instant yes/no results
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This application serves only one function - to satisfy your curiosity when you wonder whether a given number is prime or not. You put in the number, it says yes or no. Really, that's all it does.
OnClock
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.
- 20 designer font types
- Customizable gradient colors
- Adjustable time and date text size
- Background image support
- Home screen widget decoration
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Decorate your home screen with your own clock widget with OnClock. * Supports 20 types of fonts carefully selected by designers. * You can specify the gradient color yourself. * You can adjust the size of the text for the time and date. * Add a background image to create a cool clock widget. [Contact us] momots_works@naver.com https://onclock-official.blogspot.com
Screenshots
Verdict
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.
Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS
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. The most recent releases landed on September 7, 2026 and September 25, 2026 respectively.
| Parameter | Is it Prime? | OnClock |
|---|---|---|
| Price | Free — better | $0.99 |
| Rating | 3.2 (5 ratings) — better | 2.5 (2 ratings) |
| Positive reviews | 71.4% of reviews — better | 62.5% of reviews |
| Number of ratings | 5 — better | 2 |
| Update frequency | Every 74 months | Every 3 weeks — better |
| Ads | No | No |
| In-app purchases | No | No |
| Monetization | Free — better | Paid |
| Devices | iPhone, iPad, iPod — better | iPhone, iPod |
| Requires iOS | 15.0 | 14.0 — better |
| Further details — not scored | ||
| Size | 1 MB | 13 MB |
| Age rating | 4+ | 4+ |
| Developer | Wismar | AHN YOONJI |
Customer experience
Is it Prime?
OnClock
In-app purchases
Is it Prime?
No in-app purchases
OnClock
No in-app purchases
