# TachyMon vs NightBell

The clearest difference is rating: NightBell at 5.0 against TachyMon's 3.8. NightBell also leads on review sentiment (100% vs 58%) and in-app purchases (none vs 2). TachyMon's advantage is ratings volume (287 vs 3). On price, ads, device support and iOS requirement there is nothing between them.

Both are free to download. TachyMon sells 2 in-app purchases, starting at $2.99 per month. NightBell asks for nothing beyond the download.

NightBell holds the better App Store score, 5.0 against 3.8. That said, the two scores are not equally well evidenced: TachyMon has 287 ratings behind it against 3, so its average is the more settled of the two. Written reviews point the same way: 58% of TachyMon's written reviews are positive against 100% of NightBell's.

TachyMon ships an update every 3 months, NightBell every 11 days. The most recent releases landed on November 12, 2026 and November 3, 2026 respectively.

## The numbers

| Metric | TachyMon | NightBell |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [3.8 (287 ratings)](https://appshunter.io/ios/app/tachymon/id1603517412/reviews) | **[5.0 (3 ratings)](https://appshunter.io/ios/app/nightbell/id6449867229/reviews)** |
| Number of ratings | **287** | 3 |
| Positive reviews | 58.0% of reviews | **100.0% of reviews** |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | Every 3 months | **Every 11 days** |
| Monetization | Free with in-app purchases | **Free** |
| Size | 36 MB | 4 MB |
| Requires iOS | 16.4 | **16.0** |
| Devices | iPhone, Apple Watch | iPhone, Apple Watch |
| Age rating | 9+ | 4+ |
| Developer | [Whip Development Inc.](https://appshunter.io/developer/1603514887) | [Irina Deeva](https://appshunter.io/developer/1752270459) |

## What reviewers say

### TachyMon

[App page](https://appshunter.io/ios/app/tachymon/id1603517412)

Receive immediate alerts for significant heart rate fluctuations, ideal for conditions like POTS or during exercise. Customize thresholds and receive detailed event tracking. Premium features offer advanced data visualization and reporting.

**Highlights:** Customizable heart rate threshold alerts, Haptic feedback for alerts, Real-time heart rate and average display, Alert event tracking and logging, Temporary alert silencing, Detailed monitoring data review, Shareable PDF reports (premium)

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

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| TachyMon Premium Monthly | $2.99 | per month |
| TachyMon Premium Annual | $19.99 | per year |

**What reviewers like**

- 🚀 Continuous monitoring
- 🚨 Helpful alerts for heart rate spikes/drops
- 📊 Useful data tracking and visualization
- 🤖 Customizable settings and thresholds
- 💯 Accurate heart rate measurements

**What reviewers complain about**

- 🔋 Drains Apple Watch battery quickly
- 🔒 Paywalled features that were previously free
- 🤯 Buggy and unreliable at times
- 📱 Lack of companion iPhone app for data review
- 🔇 Limited notification/alert customization

**Reported bugs**

- Frequent disconnections from heart rate monitor
- Inconsistent data sync between watch and phone
- Inability to reinstall app on new devices
- Freezing and crashing issues on latest updates

**Requested features**

- Add ability to log symptoms and notes
- Implement emergency contact alerts
- Improve data export and sharing options
- Enhance graphing and trend analysis tools
- Optimize battery usage and background monitoring


### NightBell

[App page](https://appshunter.io/ios/app/nightbell/id6449867229)

This app monitors for sleepwalking episodes using motion sensors. It triggers a gentle alarm to wake you and can alert household members. A unique task-based system on a smartwatch helps differentiate between sleepwalking and being awake to prevent false alarms.

**Highlights:** Sleepwalking detection via motion sensors, Gentle alarm to wake user, Household member alerts, Smartwatch task for false alarm prevention, Designed for sleepwalker safety

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is TachyMon free?

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

### Is NightBell free?

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

### Which has better reviews, TachyMon or NightBell?

NightBell is rated higher. TachyMon averages 3.8 out of 5 from 287 ratings, while NightBell averages 5.0 from 3 ratings.

### Do TachyMon or NightBell have ads?

Neither TachyMon nor NightBell shows ads.

### Which is updated more often, TachyMon or NightBell?

TachyMon ships an update every 3 months, and NightBell every 11 days. Most recently, TachyMon was updated on November 12, 2026 and NightBell on November 3, 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.*