# Ultrasonic Repeller vs ChronStop

The clearest difference is price: ChronStop at Free against Ultrasonic Repeller's $0.59. Ultrasonic Repeller's advantage is iOS requirement (16.1 vs 26.5). On ads, in-app purchases and device support there is nothing between them.

ChronStop is free to download; Ultrasonic Repeller costs $0.59 up front. Neither carries in-app purchases, so what you see is what you pay.

## The numbers

| Metric | Ultrasonic Repeller | ChronStop |
| --- | --- | --- |
| Price | $0.59 | **Free** |
| Rating | **[3.6 (51 ratings)](https://appshunter.io/ios/app/ultrasonic-repeller/id445318668/reviews)** | — |
| Number of ratings | **51** | — |
| Positive reviews | 43.6% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 2 months | — |
| Monetization | Free | — |
| Size | 2 MB | 9 MB |
| Requires iOS | **16.1** | 26.5 |
| Devices | iPhone, Apple Watch | **iPhone, iPad, Apple Watch** |
| Age rating | 4+ | 4+ |
| Developer | [Aleksandr Balyberdin](https://appshunter.io/developer/336185043) | [Jeff Garvens](https://appshunter.io/developer/1239667481) |

## What reviewers say

### Ultrasonic Repeller

[App page](https://appshunter.io/ios/app/ultrasonic-repeller/id445318668)

This app uses ultrasound technology to create a protective barrier against insects, rodents, and aggressive dogs. It also offers features for personal space and experimental bat deterrence, with advanced controls and Apple Watch integration.

**Highlights:** Insect repellent, Rodent deterrent, Dog deterrent, Personal space protector, Apple Watch support, High-precision frequency generator, Background mode

**Features:** macOS Compatibility, Apple Watch app, Vision Pro support

**In-app purchases:** none

**What reviewers like**

- ✅ Effective on mosquitoes and insects
- ✅ Works on rodents when volume is high
- ✅ Free app with no cost
- ✅ Simple and intuitive interface
- ✅ Multiple pest settings available

**What reviewers complain about**

- ❌ Inconsistent effectiveness across different pests
- ❌ Doesn't work on dogs or older animals
- ❌ Requires high volume to be effective
- ❌ Limited range of effectiveness
- ❌ Effectiveness diminishes over time as pests adapt

**Reported bugs**

- App crashes on startup (multiple iOS versions)
- Incompatible with iOS 8 and older versions
- App force closes when screen is locked
- Crashes on iPhone 6s and later models
- No sound output on iPad 1

**Requested features**

- Add cat repeller mode
- Add bat repeller mode
- Add ant repeller mode
- Add fly repeller mode
- Add snake repeller mode


### ChronStop

[App page](https://appshunter.io/ios/app/chronstop/id6781147807)

**Features:** macOS Compatibility, Apple Watch app, Vision Pro support

**In-app purchases:** none


## Frequently asked questions

### Is Ultrasonic Repeller free?

Ultrasonic Repeller costs $0.59, with no in-app purchases.

### Is ChronStop free?

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

### Do Ultrasonic Repeller or ChronStop have ads?

Neither Ultrasonic Repeller nor ChronStop shows ads.

---

*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*