# Alarm Clock HD vs AtomicClock

The clearest difference is review sentiment: AtomicClock at 85% against Alarm Clock HD's 32%. AtomicClock also leads on rating (4.8 vs 4.5) and iOS requirement (15.0 vs 17.6). Alarm Clock HD's advantage is ratings volume (104K vs 5.5K). On price, update cadence, ads and in-app purchases there is nothing between them.

Both are free to download. Alarm Clock HD sells 10 in-app purchases, starting at $1.49 per month and AtomicClock sells 1 one-off in-app purchase. Whichever you choose, the download price is not the number that matters.

AtomicClock holds the better App Store score, 4.8 against 4.5. That said, the two scores are not equally well evidenced: Alarm Clock HD has 104K ratings behind it against 5.5K, so its average is the more settled of the two. Written reviews point the same way: 32% of Alarm Clock HD's written reviews are positive against 85% of AtomicClock's.

Alarm Clock HD ships an update fortnightly, AtomicClock every 3 weeks. The most recent releases landed on September 25, 2026 and September 24, 2026 respectively.

## The numbers

| Metric | Alarm Clock HD | AtomicClock |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [4.5 (104K ratings)](https://appshunter.io/ios/app/alarm-clock-hd/id476555713/reviews) | **[4.8 (5.5K ratings)](https://appshunter.io/ios/app/atomicclock-ntp-time/id1402993049/reviews)** |
| Number of ratings | **104K** | 5.5K |
| Positive reviews | 32.0% of reviews | **84.5% of reviews** |
| In-app purchases | Yes | Yes |
| Ads | Yes | Yes |
| Update frequency | **Fortnightly** | Every 3 weeks |
| Monetization | Freemium | Free with in-app purchases |
| Size | 230 MB | 17 MB |
| Requires iOS | 17.6 | **15.0** |
| Devices | iPhone, iPad | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Impala Studios](https://appshunter.io/developer/1063279743) | [Timo Partl](https://appshunter.io/developer/1387413672) |

## What reviewers say

### Alarm Clock HD

[App page](https://appshunter.io/ios/app/alarm-clock-hd/id476555713)

Wake up gently with your favorite music or sounds using this advanced alarm clock. It offers customizable nightstand displays, sleep tracking, and a sleep timer to help you unwind. Enjoy features like local weather and an instant flashlight, with an option to go ad-free via subscription.

**Highlights:** Unlimited alarms with Apple Music or custom sounds, Sleep tracking, Customizable nightstand display, Sleep timer, Local weather information, Instant flashlight, Screen saver for OLED displays

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

**In-app purchases (10)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Premium member - 1 month | $1.49 | per month |
| Premium Features - Weekly | $1.99 | per 7 days |
| Premium Features - Monthly | $2.59 | per month |
| Upgrade to Premium Features | $5.49 | per 6 months |
| Premium Yearly | $9.99 | per year |
| Premium Yearly | $11.99 | per year |
| Upgrade Your Alarm Clock | $14.99 | per year |
| Premium yearly | $19.99 | per year |
| Premium yearly | $19.99 | per year |
| Premium yearly | $24.99 | per year |

**What reviewers like**

- 🚀 Reliable alarm clock
- 🎨 Customizable colors
- 🔊 Ability to use music as alarm
- 💤 Gradual volume increase

**What reviewers complain about**

- 🐛 Alarm not going off
- 🔍 Difficulty seeing small buttons/text
- 💸 Subscription model for ad-free version
- 🔋 High battery consumption
- 🔇 Alarm muting phone volume

**Reported bugs**

- Alarm randomly snoozing itself
- Alarm not working when phone is muted
- Alarm sound not playing
- Alarm screen freezing/crashing

**Requested features**

- 24-hour clock option
- More alarm sounds/tones
- Ability to use own music files
- Do not disturb mode


### AtomicClock

[App page](https://appshunter.io/ios/app/atomicclock-ntp-time/id1402993049)

This app displays the exact current time synchronized with NTP servers, offering a customizable clock view for precise time checks. It's ideal for setting watches, verifying timestamps, or comparing local and network time.

**Highlights:** Precise time from NTP servers, Customizable clock faces, Select or add time servers, Local and UTC views, 12/24 hour modes, Customizable time format, Acoustic ticking

**Features:** macOS Compatibility

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Lifetime Pro Version | $6.99 | one-time |

**What reviewers like**

- 🚀 Accurate time
- 👍 Highly customizable
- 🚀 Precise to the second
- 👍 Easy to use
- 👍 Helpful for setting watches

**What reviewers complain about**

- 🐛 Server connection issues
- 🔍 Limited time zone options
- 💰 Ads diminish clock view
- 🔍 Lacks some advanced features
- 🔍 Redundant for some users

**Reported bugs**

- Crashes on certain iOS versions
- Occasional freezing of hands
- Countdown timer sound not working

**Requested features**

- Add GMT/dual time display
- Implement widget support
- Add different second hand sounds
- Allow setting background color to match watch
- Include alarm/timer functionality


## Frequently asked questions

### Is Alarm Clock HD free?

Alarm Clock HD is free to download, with in-app purchases available.

### Is AtomicClock free?

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

### Which has better reviews, Alarm Clock HD or AtomicClock?

AtomicClock is rated higher. Alarm Clock HD averages 4.5 out of 5 from 104K ratings, while AtomicClock averages 4.8 from 5.5K ratings.

### Do Alarm Clock HD or AtomicClock have ads?

Both Alarm Clock HD and AtomicClock show ads.

### Which is updated more often, Alarm Clock HD or AtomicClock?

Alarm Clock HD ships an update fortnightly, and AtomicClock every 3 weeks. Most recently, Alarm Clock HD was updated on September 25, 2026 and AtomicClock on September 24, 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.*